use italics for the titles of complete books, plays, edited volumes, anthologies or journals
use single inverted commas (quotation marks) for sections of books, e.g. the titles of individual poems, short stories, articles within a journal, essays within an edited volume
make sure you apply the capitalization rules of different languages for titles: they are often different from English. A concise set of rules for each language is set out in the MHRA Style Guide, downloadable from the MHRA website.
avoid inelegant contractions or the use of initials for titles, e.g. TJE for La tía Julia y el escribidor; instead choose a shorted version of the title, e.g. La tía Julia.