Member David Lindwall's article
got Guatemala? was published in
the March 2019 issue of
The American Philatelist. APS members
may read the article online here.
The March/April issue of Topical Time,
the journal of the Americal Topical
Association, contains two articles on
Mayan topics on stamps.
Cherrystone is one of the few auction houses in the US that regularly has Guatemalan material. In their February 1-2 auction they are offering a large collection of Guatemalan stamps from what appears to be an old-time collection.