The principal question for our determination in this appeal, triable de novo, from the order of the Secretary of State denying sufficiency of the involved initiative petition, hereinafter described, is as to whether a sufficient number of registered legal voters in fact did sign the petition.
The Secretary denied sufficiency of the petition on the ground of its alleged unconstitutionality without referring to the number of valid signatures.
Pursuant to order, hearing was commenced April 5, 1972 to determine factual issues relating to Initiative Petition 288, State Question 480. Hearing was concluded August 22, 1972, and record of proceedings filed October 2, 1972. As the Secretary of State’s final order made no determination of total number of signatures on the petition, the parties stipulated the petition bears 144,624 signatures.
Based upon evidence adduced, the Referee found stated facts established by fair preponderance of evidence, from which conclusions of law hereafter set forth were determined. The stipulated gross total of signatures affixed to the petition requires 104,818 valid signatures for submission of the proposition to the electorate. A total of 698,790 votes were cast for office of the Governor in the November 8, 1970 general election. Computed as fifteen percent of that total, 104,818 valid signatures are required to place this proposal before the electorate. Successful challenge to 39,807 signatures would render the petitition invalid.
Exhibits introduced by the parties disclose 33,709 signatures of persons either not registered voters during circulation interval, or who registered during the interval but after signing the petition. The fact of non-registry rendered these signatures invalid. In re Initiative Petition No. 142, State Ques. No. 205, 176 Okl. 155, 55 P.2d 455.
The petition bears 135 admittedly illegible signatures, from which identity of the signers cannot be ascertained. Only a registered voter can sign an initiative petition. 34 O.S.1971 §§ 3, 6, 23. Initiative Petition 142, State Ques. 205, supra. Illegibility precludes determination of a signatory’s eligibility as asserted by proponents and agreed by contestants.
On pamphlets circulated by persons not registered voters contestants challenge 2,355 signatures. Contestants urge the words “legal voter”, appearing in 34 O.S. 1971 § 3 concerning signers, bear the same meaning as the words “qualified elector” in Section 3.1 relating to petition circulators. Proponents assert a circulator need not be a registered voter to be a qualified elector. In challenge of these related signatures proof was limited to the circulator’s non-registration as a voter.
Constitution Article III, Section 1 declares qualifications of qualified electors. “Qualified electors of this state shall be citizens of the United States, citizens of *1092the state, including persons of Indian descent (native of the United States), who are over the age of eighteen years and who have resided in the state at least six months, in the county two months, and in the election precinct twenty days next preceding the election at which such elector offers to vote. * * * ” Registration to vote is not a prescribed qualification. Prior to 1969 enactment of 34 O.S.1971 § 3.1, no statutory qualifications were prescribed for petition circulators. For this reason the court refused to invalidate signatures affixed to petition circulated by minors. In re State Question No. 138, 114 Okl. 285, 244 P. 801 (1926).
Legislative enactment of § 3.1 accomplished with knowledge of problems existing theretofore, attempted no differentiation or change in identity and qualification between electors and legal voters. Also see 34 O.S.1971 § 6 which relates to verification of signatures by the circulator. In this verification the circulator verifies that he is a “qualified elector”, and that “each signer is a legal voter.” This court cannot speculate as to legislative intent, or question propriety of particular enactments. Whether restrictions should be imposed, or qualifications of future petition circulators defined are matters purely of legislative concern. Had the Legislature intended petition circulators to be only registered voters this could have been accomplished by slight change in the language used. Since this was not done we are of the opinion the Legislature intended no such qualification. We hold that our statutes make no requirement that petition cir-culators be registered voters. There being no proof the circulators were not qualified electors, the signatures challenged on this ground are valid. Contestants challenge of 495 signatures under their Exhibit 140 and 140-A is not supported by any evidence to show the circulator involved was not a qualified elector.
Another category involves 2,199 signatures challenged as invalid either because subscribed out of the circulator’s presence, or acknowledgement by circulator in making his affidavit was improperly performed. A total of 829 of these signatures are invalid for these reasons. Complete review of the evidence is unnecessary. On some challenges contestants insist a circulator, having made his affidavit, thereafter responded to contestant’s questionnaire in such manner as to impeach the .affidavit. These circulators testified signatures either were affixed in their presence or were able to identify particular signatures which were, or were not, affixed in their presence. Absent other proof, admission as to falsity destroys probative value of the affidavit and requires exclusion of the entire pamphlet. However, a circulator’s testimony which redeems properly affixed signatures from challenge is sufficient to prove affirmatively those signatures properly were affixed within the rule in In re Initiative Petition No. 145, State Ques. No. 215, 187 Okl. 284, 102 P.2d 189; Milburn v. State Taxpayers Ass’n, 114 Okl. 285, 244 P. 801; In re Initiative Petition No. 142, State Question No. 205, supra.
Further challenges in this category were because a witness was unable to recall positively whether she appeared before the notary public taking the acknowledgement, months after the fact. The affidavit is not impeached by this testimony, since obviously given in consequence of the witness’s meticulousness in testimony, rather than from real or well founded doubt.
Other challenges assert certain signatures were affixed at a place sufficiently far removed as to be out of the circulator’s presence. One challenged pamphlet was circulated by a bartender, who observed subscription of signatures several feet across a room. Such challenges are hyper-technical and do not effectively challenge signatures other than those declared invalid.
Further challenge of 1,015 signatures is made by reason the name of the same signer appears on the petition more than once. No legal voter properly can affix his signature to a petition more than one time. When a signature is duplicated *1093the duplicated signature is to be disregarded. In re Referendum Petition No. 35, State Question No. 101, on House Bill No. 509, 78 Okl. 47, 186 P. 485. Disregarding each duplicated signature would impose a burden not contemplated by the law. One of each duplicated signatures not otherwise successfully challenged is valid. In this category 671 signatures are declared invalid.
One witness, testifying as a handwriting expert by stipulation, sought to prove that 951 signatures were affixed by someone who subscribed more than two names. The only proof adduced was the witness’s opinion, and no effort was made to distinguish signatures, or establish lack of authenticity by presentation of an exemplar. Under this state of the evidence this expert testimony fails to support contestants’ claim of total invalidity. Our decision in In re Referendum Petition No. 71, State Ques. No. 206, 179 Okl. 381, 65 P.2d 985, concerning similar testimony, states that upon such testimony alone the court cannot strike the names of petition signers, nor attribute corrupt motives to circulators so as to invalidate signatures they obtained. Related evidence is insufficient to overcome the presumption of validity as to all challenged signatures. We find invalid 460 signatures challenged on this ground. In re Initiative Petition No. 145, State Ques. No. 215, 187 Okl. 284, 102 P.2d 189.
Other signatures (167) are challenged because the persons signing, residents either of Oklahoma City or Tulsa, each failed to give a street address. These challenges are proper under the rule announced in In The Matter of Referendum Petition No. 119, State Ques. No. 381, Okl., 339 P.2d 530. However, of this total there are 34 challenged also as unregistered. Success of one challenge renders moot another challenge to that signature. Of the 167 signatures 133 are validly challenged. The remaining 34 challenges are ineffective, having been challenged on other grounds.
Further challenge is directed to 102 signatures which failed to give a post office address, and to 171 signatures where the signer gave “City” as a post office address, but with a street address patently in Oklahoma City. Challenges are proper as to 102 signers involved who omitted any post office address. Although the practice of giving “City” as an address is not strictly in accordance with statutes, supra, this is a generally understood usage and contestants were not disadvantaged by this abbreviation, and challenge on this ground is intrinsically technical.
In this same context 6,205 signatures are challenged because signers used “OC”, “OKC”, “MWC”, “B’ville”, and like abbreviations. Where generally understood such abbreviations are technical violations, unless a contesting party actually is prejudiced thereby. Contestants showed no resulting prejudicial burden and these challenges are not well taken.
Other challenges are asserted on various grounds by contestant’s Exhibit 257. One pamphlet of 37 signatures is unverified by omission of signature by the person taking the circulator’s acknowledgement. The signatures are invalid in view of 34 O.S.1971 § 6. On pamphlets containing 119 signatures the circulators attempted to take his own acknowledgement, and these are rendered invalid. In re Initiative Petition No. 224, State Question No. 314, 197 Okl. 432, 172 P.2d 324. Also challenged are 47 signatures on pamphlets whereon the circulator’s verification was before a notary public whose commission had expired. We determine a total of 203 challenged signatures invalid. Remaining challenges by contestants under Exhibit 257 are deemed to be technical only, within the law announced in In re Initiative Petition 224, State Question No. 314, 197 Okl. 432, 172 P.2d 324, 327.
Challenges are made (Exh. 260) to pamphlets which bear defects relating to circulators, as 449 signatures where the circulator failed to give a sufficient post office address, the asserted defect *1094being a varying abbreviation of Oklahoma City. In each instance the post office address is readily determinable although abbreviated. We hold this to be substantial compliance with the statutes. Also challenged are 176 signatures on pamphlets whereon the circulator gave only Tulsa or Oklahoma City as an address. We hold this challenge specifically within our ruling in In re Initiative Petition No. 272, State Question No. 409, Okl., 388 P.2d 290, 294, and find these 176 signatures invalid. Challenge to six signatures is because the circu-lator signed the petition which he circulated and certified his own signature. No basis exists in the law for such challenge. Contestants also have challenged 1,963 signatures on pamphlets where the circulator’s name in the affidavit varies from Affiant’s subscribed signature. This is a technical objection, and the affidavit is deemed suf-cient under 34 O.S.1971 § 6.
Challenge of 231 signatures is on the ground some persons inscribed multiple names. On one pamphlet 16 signatures were subscribed in spaces provided for verification of signatures, the signers names then were printed on the signature side. No doubt is cast on genuineness of these signatures, the challenge being based entirely upon this reversed use of two sides of the petition. Other signature pamphlets (Ex. 267-272) are challenged by testimony of the expert witness that multiple signatures were subscribed by one person. This opinion evidence, considered in conjunction with physical examination of pamphlets containing challenged signatures, is insufficient to overcome the presumption of validity, and these signatures are valid.
One pamphlet containing 40 signatures was inadvertently verified by one Kune, although in fact circulated by another. Signatures on this pamphlet therefore are invalid. Contestants challenge to other pamphlets circulated by Kune is without basis. Inadvertent verification of one pamphlet does not destroy validity of others which are properly verified.
Contestants challenge 26 signatures on basis of the handwriting expert’s opinion testimony these signatures were subscribed by the circulator of petitions from which these pamphlets were detached. Challenged signatures are predominantly those of local residents, but no proof was offered relating to the least inquiry of the signers. These signatures are valid on basis of the legal presumption of validity which was not overcome by the quantum of proof adduced.
Another challenge concerns the name of Mrs. Ballyeat which appears on a pamphlet circulated by Sturm and on another circulated by Clark. Sturm testified Mrs. Ballyeat signed her petition, but Bal-lyeat testified she signed only the Clark petition. Mrs. Ballyeat properly could sign but once. The duplicate signature is not challenged elsewhere. This one signature is invalid. Absent showing of guilty knowledge or intentional wrongdoing, remaining signatures on the Sturm circulated pamphlet are not impeached.
Eighteen signers gave addresses outside Oklahoma. It may be assumed those persons are non-residents, and therefore ineligible to lawfully sign this initiative petition. 34 O.S.1971 § 2.
Petition counterparts bearing 315 purported signatures were circulated by one Kraker. These were challenged as invalid and invalidity was confessed by proponents. Four other pamphlets containing 133 purported signatures were challenged and the invalidity confessed by proponents. Under this finding a total of 448 signatures are invalid.
A total of 713 signatures are challenged on the ground some were improperly certified on the reverse sides of the signature pamphlet. Challenge often is based upon respective versions of the circulators as opposed to versions of contestant’s staff members. Numerous challenges are based upon minor variations. Of the total challenged, there are 221 instances where the circulator’s manner of certification is so improperly done as to require sustaining challenges to the related signatures. As to contestants remaining challenges under this category (Exh. 209-209-A), we conclude *1095these are not well taken, since there is substantial compliance with 34 O.S.1971 § 6.
The initiative petition bears a total of 107,478 valid signatures after deduction of 37,146 successfully challenged signatures. Contestants have challenged a total of 53,165 signatures. The facts found heretofore have adjudicated 51,765 challenges. Challenges to 1400 signatures have not been dealt with specifically. This seeming discrepancy results from tandem or duplicate challenges. Even assuming these challenges are not duplicate or tandem, and that all were sustained, validity of the petition still would be established.
We decline consideration of the issue advanced by contestants relative to asserted constitutional invalidity of the current initiative petition. Threadgill et al. v. Cross, 26 Okl. 403, 109 P. 558 (1919).
From examination of the entire evidence we conclude the petitions are valid in the form required by statutes, and signed by a sufficient number of legal voters of this state, and the proposed amendment should be submitted to the people for determination.
DAVISON, V. C. J., and WILLIAMS, JACKSON, IRWIN, LAVENDER and SIMMS, JJ., concur. HODGES, J., concurs in part, dissents in part. BARNES, J., dissents.