Went back and re-read, still not seeing it there. It is described in the linked wikipedia article, though: https://en.wikipedia.org/wiki/Decimal_degrees https:

Went back and re-read, still not seeing it there. It is described in the linked wikipedia article, though: https://en.wikipedia.org/wiki/Decimal_degrees https://en.wikipedia.org/wiki/Decimal_degrees, so it isn't completely ignored by the author.