I’ve already written about the correct use of reflexive pronouns in This Redundancy Is Self-Evident, but several people still wanted confirmation on the use of words such as hisself.
The indefinite pronouns are myself, ourselves, yourself, yourselves, herself, himself, themselves, oneself, and itself.
Hisself, theirselves, theirself, ourself, and oneselves are not legitimate words; they are, rather, what you would call grammar errors. You can also call them substandard grammar. Actually, you can call them anything you want; just don’t use them in either speech or writing, casual or formal, with friends or at work, in your thesis or in your office memo, when you’re at dinner or at the roller derby, at a hockey game or at the opera….