Mexico Used Collection.
To about 1950 in a Schaubek album, many elusive stamps that were purchased individually at auction or from reliable dealers, early issues include better district overprints, cancels, and a few multiples, later include Civil War issues, as well as key stamps and high values of definitive issues, Air Post, Officials, and other Back-of-Book, seven stamps (Nos. 40, 228, 264, 268, 327, CO30 and O21) with Mepsi certificates, and No. 229 with Sismondo certificate, also of note is the 1934 University Air Post set, with the 20p high value on cover, largely Fine-Very Fine
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