Multiple citations from an author in one year

I know this is an old thread, but this is a very real issue, and not the result of some authors and editors being clueless. Most of the journals and other publication guidelines in my field are standardized on American Antiquity style, which requires that works by the same author and year appear in the order cited in both the in-text citations and the references cited.

For example, (Smith 1997b) should not appear before Smith (1997a) in the text. If I cite Smitth (1997a) it should be the first “Smitth 1997” to be cited and it should also appear first in the bibliography, regardless of title alphabetization:

Rodgers, K. (2000) Some Great Stuff. Journal of Stuff 14:34-40.
Smith, J. (1997a) Better Living. Journal of Studies 54:1-4.
Smith, J. (1997b) Absolute Zero. Journal of Investigation 32:45-49.
Ubelaker, D. (1967) Old Fashioned Living. Journal of Studies 24:56-58.

I am sure it isn’t this easy, but what happens if you set the output style for  bibliography to do a custom sort based only on first author and then Year?  then the years do come out in order of appearance, but I am sure something else will be wrong… but so far, everything I throw at it, came out okay?  

I edited to add YEAR as I read the instructions further , to find they needed to be in chronological order as well. This didn’t break the order of appearance for a and b.

using this source: