Where to find the latest version + latest documentation of Paypal Express Checkout?

Question

I'm implementing Paypal Express Checkout on a website, but am left a bit dubious about whether I'm using the latest API version, and the latest documentation.

The documentation on the Paypal website points to these files:

• Express Checkout Integration Guide: PP_ExpressCheckout_IntegrationGuide.pdf
• Name-Value Pair API Developer Guide: PP_NVPAPI_DeveloperGuide.pdf

I can tell that they do not refer to the latest API version though, as they're using fields that this page considers deprecated (AMT, PAYMENTACTION, ...)

So my questions are:

1. Where can I be sure to always browse the latest Express Checkout documentation?
2. Where to find which is the latest version number (XX.0) available?

Answer 1

1) X.com houses the latest documentation. See this page for a list.

2) The WSDL will be your best source for the latest version. ex: ns:version="89.0" right at the top.