ziomal Obama
ziomal Obama voted up Anonymous' answer
You include the words "Figure reprinted from", or, if you have added significant elements to it, "Figure adapted from", followed by a proper bibliographic reference to the original source. It is good practice to ask for permission from the original authors to reproduce their figures in your thesis. (Especially if they are on the jury … Read more
ziomal Obama
ziomal Obama voted up Annabella Grikk's answer

Well, I believe this depends on the referencing style you should use. And the best guide to this is the one from purdue.edu. For example, in Chicago style, this looks like this:

Fig. 1. Alice Neel, Nancy and the Rubber Plant. 1995, Oil on canvas, 203.2 x 91.4 cm. The Estate of Alice … Read more