[...trimmed text...]

It sure looks like they gave credit to the ulitmate source to me. Right at the top:

The Brettschneider equation is the de-facto standard method used to calculate the normalized air/fuel balance (... Login to read more.

iATN Members:
Login to read this message and participate
Auto Repair Pros:
Join iATN to read this message and others
Vehicle Owners:
Find a nearby iATN member to repair your vehicle