(2) In an indictment for aiding, abetting, counselling, suborning, or procuring any other person to commit any offence hereinbefore in this section mentioned, or for conspiring with any other person, or with attempting to suborn or procure any other person, to commit any such offence, it is sufficient-- (_a_) where such an offence has been committed, to allege that offence, and then to allege that the defendant procured the commission of that offence, and (_b_) where such offence has not been committed, to set forth the substance of the offence charged against the defendant without setting forth any matter or thing which it is unnecessary to aver in the case of an indictment for a false statement or false representation punishable under this Act. =13.= A person shall not be liable to be convicted of any offence against this Act, or of any offence declared by any other Act to be perjury or subornation of perjury or to be punishable as perjury or subornation of perjury solely upon the evidence of one witness as to the falsity of any statement alleged to be false. =14.= On a prosecution (_a_) for perjury alleged to have been committed on the trial of an indictment for felony or misdemeanour, or (_b_) for procuring or suborning the commission of perjury on any such trial, the fact of the former trial shall be sufficiently proved by the production of a certificate containing the substance and effect (omitting the formal parts) of the indictment and trial purporting to be signed by the clerk of the court, or other person having the custody of the records of the court where the indictment was tried, or by the deputy of the clerk or other person, without proof of the signature or official character of the clerk or person appearing to have signed the certificate. =15.= (1) For the purposes of this Act the forms and ceremonies used in administering an oath are immaterial, if the court or person before whom the oath is taken has power to administer an oath for the purpose of verifying the statement in question, and if the oath has been administered in a form and with ceremonies which the person taking the oath has accepted without objection, or has declared to be binding on him. (2) In this Act-- The expression “oath” in the case of persons for the time being allowed by law to affirm or declare instead of swearing, includes “affirmation” and “declaration,” and the expression “swear” in the like case includes “affirm” and “declare”; and The expression “statutory declaration” means a declaration made by virtue of the Statutory Declarations Act, 1835, or of any Act, Order in Council, rule or regulation applying or extending the provisions thereof; and The expression “indictment” includes “criminal information.”