I am currently researching the postal history of Mexico for my site I am currently researching the postal history of Mexico for my site
http://www.stampworldhistory.com/. And, I am looking for information on the stamps issued during the period of the Mexican Revolution 1913-1916. I know the most important resource would be Nicholas Follansbee's 'Stamps of the Mexican Revolution 1913-1916', but that is only available in hardcopy - and somewhat beyond my budget.
Does anybody know good online resources on the subject?