Le Blanc

Hello everyone, Recently I discovered I have a Norman Baxter pencil sign print 27" x 20" of the City of Houston prior to the Astrodome, It shows the old coliseum. My mom was an artist and new him and he gave this print to her. It is also on the left bottom side numbere 40/200 in pencil also. It is on some very heavy paper, Does anyone know what I hae and if so, what do you think it is worth today. Not that I want to sell it, just curious. Thanks so much for you time. Jim