Source : Free On-Line Dictionary of Computing

GSL
     
        Grenoble System Language.  M. Berthaud, IBM, Grenoble.  "GSL
        Language Reference Manual", M. Berthaud et al, March 1973.  "A
        MOL-Based Software Construction System", M. Berthaud et al, in
        Machine Oriented Higher Level Languages, W. van der Poel, N-H
        1974, pp.151-157.