named after the book A Programming Language
Specifically: APL\360
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FORTRAN IVFORTRAN IV
Fortran; formerly FORTRAN, derived from Formula Translation) is a general-purpose, compiled imperative programming language that is especially suited to numeric computation and scientific computing.
dBASE IIdBASE II
… suggested calling the new product version two (“II”) to suggest it was less buggy than an initial release. Ashton-Tate