Where I can find information on the Canny algorithm used by matlab edge function?

I have been studying the code of matlab edge function to understand the canny algorithm. This function does not excatamente follow the same steps as the original Canny algorithm. For example, the maximum suppression of non linear interpolation used. Indeed, in this way, it works much better than the original canny algorithm.

Where I can find information on the Canny algorithm used by matlab edge function?

Best Regards,

B.