Ask HN: Books on Payment Card Industry

Hi HN,

I'm a complete NEWB when it comes to understanding PCI. What I want to understand (preferably deeply) is how the PCI works especially with examples like what makes square, balanced, braintree and paypal different? Where do these services sit between the customer, the bank and the merchant etc. Any references in form of books, blogs, papers would be greatly appreciated!

PS: I'm not looking for information regarding PCI-DSS and PCI compliance.