From tekhelet.com:
“Dr. Greenspan is a co-founder of the Ptil Tekhelet Association. He is a US trained dentist, with a practice in Jerusalem. He is a mohel, shochet and sofer, and has worked for more than 20 years on collecting Jewish traditions and mesorot from far flung Jewish communities. He has lectured around the world for Dental groups and for many Synagogues and Jewish Schools.
Multimedia Presentations include:
Tekhelet, Halachic Archeology, Halachic Adventuring, Mesorah of Exotic Kosher Animals, Search for the Perfect Etrog, History of Matzah. His writings can be accessed at:
http://halachicadventures.com/”