As I recall, according to "Strunk and White", and the "Chicago Manual of Style", all punctuation is supposed to be included inside the quote characters.

I happen to disagree with them, but they have been considered authorities on the proper way to write in the English language for many decades.

American style (Chicago, APA, and MLA) specifies that a period goes inside the quotations.

British style, on the other hand, specifies that a period goes outside the quotations.

http://blog.apastyle.org/apastyle/2011/08/punctuating-around...