A manual for writers of research papers, theses, and dissertations, 7th edition - Kate L. Turabian 2007
Parts of published works
Numbers
Part III. Style 20 spelling
Numbers in parts of published works are given in arabic numerals, regardless of the general rule (see 23.1.1) or their appearance in the work itself. See also 22.3.2.
chapter 14
part 2
act 1, scene 3