hello everyone,

Some graphs in my thesis are from past co-authered papers. Is that necessary to make quotation in every case of graph. I am thinking about using an appendix to carify the boundary of collaboration work, as that will be looking-nice.

Also, in the introduction part of my thesis, some classic graphs are based on textbook. I mean I draw it myself and make some modifications. But they are still looking similar with some graphs in other's publications. Should I make quotation in this case as they are all background information.

Have you guys got same problems? Looking forward to your tips.

If you want to include graphs from textbooks etc, you normally modify it slighty (like you have) and then say "modified from Smith et al. (1978)" or however you reference.