There are two issues here: Should you use one or two l's? And, if your choice is different from that used in the title of a work that you are citing, what do you do?
The second question is easily answered. ALWAYS give a title in a citation as it was published. It is very common for Americans to cite British books or vice versa, or for modern writers to cite a book written hundreds of years ago when the language was slightly different. Don't "translate" a title to your dialect. This just makes it difficult for a reader to properly identify the work being cited. I suppose a minor spelling change wouldn't be likely to confuse, but you really don't want to cite Shakespeare's "Taming of the Shrew" as "Domestic Violence Against a Woman for Violating the Social Norms of Her Day" to accommodate modern readers. I suppose if the book is old enough it might qualify as a foreign language and then you're moving into a different category.
As to one "l" versus two: I live in the U.S. When I was a kid in school, I was taught that if a word ends with a single consonant, that when you add -ed or -ing to that word, you double the consonant. So "model" should become "modelling". This makes good sense to be because it preserves the usual pronunciation rules: a vowel followed by a single consonant is long, but a vowel followed by two consonants is short. But apparently this is not the current convention. I generally go with what my spell-checker says, which seems a cop-out approach to language -- oh, do you always just do what you're told? -- but it's easier to be consistent that way.