I'm writing my master thesis in mathematics and yet I should also use definitions.
Here the question is if I just may take from one side a definition if this definition is well known (ie is used on many different pages) or if I mark it must quote? If so, what name should I then write down there, because the author of the page will probably have found the definition hard itself.
I thank you in advance for any replies.
The best answer
Basically, all that is taken literally you have to characterize as a quotation and was what indeed written at all, in their own words, but the spirit of by whom different dates has also a source reference are given. Because it does not matter how well known the definition is. It is best if you can find out who has made the definition originally and then quoting from the original work, if that is too complicated, you can also change according to the work indicate where you have it found. And specify the author even when Internet sources. Mostly is the somewhere, at least at official and reputable sites, from everything else is allowed in skilled work ner eh put your fingers;)
If you abschreibst literally from one side, you have to specify the page. If the author of the book not inst the author of the definition, he is still the one who has placed them in this form in this book. That's why you gibtst to the author (or editor) of your source.