That looks fine, but please can you add a complete citation? Family Search make it very easy to copy the citation on the left hand side with the "Copy citation" button. Rather than add Martha as an Unknown, it's a good idea to see if you can find some information about her first.
Edit Oh dear I'm just as bad not reading the register properly! Yes, it looks good. I don't see Mary Parson mentioned though. Did you post the right link?