Nebraska Revised Statute 28-422
Chapter 28
28-422.
Selling or offering for sale certain compounds; register; maintain for one year.
Every person selling or offering for sale at retail any of the substances as defined in section 28-419, shall maintain a register in which are recorded the date of each sale, the quantity sold, and the name and address of the purchaser. The record of each sale shall be available for inspection by any peace officer for at least one year.