DSHA shall have a corporate seal in the form of a circle bearing the arms of the State in the center and the name of DSHA in the border. All deeds, contracts or other obligations, certificates or other instruments executed, including bonds which are provided for in § 4017 of this title, made or issued on behalf of DSHA, shall bear the signature of the Housing Director and have impressed or imprinted thereupon the seal of DSHA, or facsimile thereof, and when so appearing shall be conclusively presumed in any judicial action or proceeding the valid act and deed of DSHA. The presumptions set forth in this provision shall also apply to all bonds executed pursuant to § 4016 of this title.