# If part of a textbook is quoted how should it be referenced?

What are the rules when copying examples from text books? For example is it allowed and if so how should the textbook be referenced (e.g. included the name and author?). In particular I'm wondering about this question about BAN logic where I took a screen shot from a PDF version of the textbook (which I own) and find it much preferable than retyping everything using Latex.

Part of the problem is it would be very difficult to translate the notation into MathJax/Latex.

• The part about scan seems to be related to this older post: On the inclusion of pages-of-text-as-images in questions. See also other questions linked there. – Martin Sleziak Oct 13 '15 at 6:16
• I think MathJax is preferable to images, as the former are downloaded more quickly and are searchable. – Joel Reyes Noche Oct 13 '15 at 6:16
• If you ask question directly from some book you should definitely say what the source of the question is. There is no policy about the way you have to format citations. – Martin Sleziak Oct 13 '15 at 6:19
• Translating the formula into LaTeX wouldn't be that difficult... Look at how the one who answered your question did it for future reference. – Najib Idrissi Oct 13 '15 at 9:34
• @NajibIdrissi thanks for your opinion, it would've been difficult for me as I don't know the name of the operators to look up how they're respresneted in LaTeX. – Celeritas Oct 13 '15 at 10:05
• @JoelReyesNoche how is MathJax searchable? – Celeritas Oct 13 '15 at 10:06
• Now you have added one more question, asking what to do if you do not know how to typeset something using LaTeX. It is perfectly fine to ask on about problems with MathJax, in particular, how to typeset some specific symbol or formula. We had such questions; one example is here; you might find more similar posts in (mathjax) tag. And even posting a picture is good option in such case - there is a chance that somebody (a magical fairy) will edit your post and you will learn from their edit. – Martin Sleziak Oct 13 '15 at 10:34
• @Celeritas, a search for a^2+b^2 in any search engine would be able to find the text $a^2+b^2$ but not an image containing that text. – Joel Reyes Noche Oct 13 '15 at 12:44
• @JoelReyesNoche my understanding is LaTeX is generally not searchable. e.g. math.stackexchange.com/questions/1055538/… – Celeritas Oct 13 '15 at 19:51
• Also it's a moot point about the searchability of the equation: I was asking what one operator does and it's not as if someone's going to happen to search that exact same equation. – Celeritas Oct 13 '15 at 23:19
• An important reason to use MathJax over images is that MathJax can be used in conjunction with screen readers so that visually impaired users can understand the mathematics, whereas that is not possible with with images in general. – Davide Cervone Oct 14 '15 at 9:16