Media praise for PayPal APIs: Up and Running
"Developers looking at transaction services must have this reference to a key internet commerce component."
-- , The Midwest Book Review: The Bookwatch, August 2011, Volume 6, Number 8
"A worthy upgrade to the first edition, this time not PHP but enumerated in Python. Does a good job of plotting & describing PayPal's increasingly byzantine "workflows" to bop payments back and forth."