That could be a pretty tough call, half of all Anubias in the trade are actually cultivated varieties of the Anubias barteri. For example one shop/nursery labels Anubias Bonsai, the other A. nana. or A. petite or any combination of this for the exact same variety, then there are others with other fantasy names that are still A. barteri.
See this database, they display about all in the trade...
TODO
www.flowgrow.de
Look at their description and the detailed characteristics of your plants and make a pick that comes closest to you.

Then it still could be a tough call if you don't know if the ones you have are young or mature.
I once got my hands on an Anubias Ducky... Duno what it is, some other A. barteri or? Just a Ducky?... But it doesn't quack...