I wouldn't go as far as to say Gaspipe is a great book. Like Tyler said, it's filled with errors and inaccuracies and that is why I have a big problem with that book. It does mention a few interesting things, including the name of one FBI agent who supposedly was on Casso's payroll.
if i remember correctly (i liked the book, i know it had its share of errors) but i think the book they just mentioned he had an fbi agent they never actually mentioned his name i believe i could be wrong...
