BRANDAID: A Marketing-Mix Model, Part 2: Implementation, Calibration, and Case Study." Little, John D.C. Operations Research Vol. 23, No. 4 (1975): 656 - 673.
An Algorithm for the Traveling Salesman Problem." Little, John D.C., Katta G. Murty, Dura W. Sweeney and Caroline Karel. Operations Research Vol. 11, No. 6 (1963): 972-989.