The article is wrong in attributing "open source" to Eric Raymond alone. As it's now used, it was apparently coined by Christine Patterson and mutually agreed to at a meeting where Eric Raymond was present in February 5, 1998. [1]

According to the release history, "The Cathedral and the Bazaar" was written in 1997, but originally used the term "free software". The term was changed to "open source" on February 9th. [2]

[1] https://opensource.com/article/18/2/coining-term-open-source... [2] http://www.catb.org/~esr/writings/cathedral-bazaar/cathedral...