Lombardi, Lionello "On the control of the data flow by means of recursive functions" pp173-186

(1962) Symbolic Languages in Data Processing, in the Proceedings of the Symposium organized and edited by the International Computation Centre, Rome, Italy, March 26­31, 1962, Gordon and Beech Science Publishers, 1962.  

Languages mentioned ABL {1960} Language manipulation of files ADSL {1962} Algebraic Data System Language