Bloch was a member of the Friedl Expert Committee which specialized in the expertizing of rare European stamps.

"From Civilizing to Expertizing Bureaucracy: Changing Educational Emphasis in Government-Supported Schools of Tokyo (Edo) during the Tokugawa Period and Early Meiji Era."

These and 29 other items, United States and foreign, are described in "Opinions VI: Philatelic Expertizing, an Inside View," the sixth in a series published by the foundation, a private educational and research group that charges a fee for expertizing.