As others have stated, there are no absolute authorities or rules on English punctuation. However, there are certain guidelines that are helpful. Rather than putting my foot in my mouth by trying to list or explain such guidelines, I point you to two useful resources. - The Chicago Manual of Style https://books.google.com/books/about/The_Chicago_Manual_of_Style.html?id=4xJIAQAAIAAJ&source=kp_cover&hl=en see also http://en.m.wikipedia.org/wiki/The_Chicago_Manual_of_Style - Elements of Style https://books.google.com/books/about/Elements_of_Style.html?id=K23rAgAAQBAJ&source=kp_cover&hl=en I recommend you read there not only about hyphens, but about _en-dashes_ and _em-dashes_ as well, as people (even native speakers) are often confused about when to use which. Keep in mind that the above references are only two author's opinions. They are not "cast in stone". Others here can probably point to other good resources re hyphenation. (I specifically do NOT recommend _**Eats, Shoots and Leaves**_, because Ms. Truss does not distinguish between hyphens, en-dashes, and em-dashes; rather, she calls them all "dashes".) Again, remember that opinions vary. See, for example other questions about hyphens on this forum. [editors please add link?]