All reports filed with the National Oceanic and Atmospheric Administration must be dated and signed by or on behalf of the person conducting or intending to conduct the weather modification activities referred to therein by such person, individually or, in the case of a person other than an individual, by a partner, officer, or other person having corresponding functions and authority. For this purpose “officer” means a president, vice president, treasurer, secretary, or comptroller. Notwithstanding the foregoing, such reports may also be signed by the duly authorized agent or attorney of the person whose activities are being reported. Proof of such authorization shall be furnished to the Administrator when filing a report, unless previously furnished.