Whenever any person, firm or corporation within this State ships or delivers to a purchaser within this State any shell eggs that have been in storage or processed, such person, firm or corporation shall deliver to the purchaser an invoice or bill showing thereon the character of such eggs. All containers of shell eggs deposited in cold storage must be marked plainly with date of receipt and date of withdrawal by the officer, or the officer's agents, in charge of the cold storage plant.   [RR 2021, c. 1, Pt. B, §92 (COR).]