How do you find out the series of the 1928 silver certificate

I assume you are asking about the value, right? Condition is as important as year and we don't know if you bill is well worn or uncirculated. This is just a start for you What is the value of 1928 silver certificate dollar bill (http://wiki.answers.com/Q/What_is_the_value_of_1928_silver_certificate_dolla r_bill) You should get it appraised by someone who deals in old money and could maybe make you an offer.

No I am asking how to tell the series be it a,b,c,d or e because there is no number beside the year on the 1923