My memory of the whole "nGL" language thing was that it was more a marketing term than anything you would find in an academic paper. It was particularly common

My memory of the whole "nGL" language thing was that it was more a marketing term than anything you would find in an academic paper. It was particularly common in the IBM world, for example in books[1] and advertisements[2] [1] https://www.oldcomputerbooks.com/pages/books/R504/james-martin-inc-joe-leben-the-arben-group/4gl-fourth-generation-languages-volume-iii-4gls-from-ibm-adl-adrs-ii-apl-as-csp-dms-gis-ic-1-sql-qbe-and https://www.oldcomputerbooks.com/pages/books/R504/james-mart... [2] I can't find a good example, but I remember seeing ads for "4GL" tools in Dr Dobbs regularly in the mid-90s.