Thanks for the suggestions and alternatives to how to add credit or refer to it. Though I didn't really want to know how to sign off my own work.
Oh so, what I wrote was right?
I was trying to refer to a picture that was drawn. I wanted to speak in third person about who made it. I am aware of работа and труд as words so far, but I wasn't sure which was better to use in this case. I guess I better start reading those grammar books I have now haha.