Not sure if book recommendations are allowed, but I'm looking for a reference book that contains details about a wide variety of languages, written for linguists. For example, let's say I wanted to know the word order of Polish, or the written script of Urdu, or the basic grammar of Korean, etc. A book that contains a reasonable summary of the nuts and bolts of most languages. Not as a resource for learning the language, just as a reference for an overview of the language.