Mathematics and Computers in Soviet Economic Planning. Richard Roll; John P. Hardt; Marvin Hoffenberg; Norman Kaplan; Herbert S. Levine Journal of Financial and Quantitative Analysis 1968 3(3), 363
Mathematics and Computers in Soviet Economic Planning Eberhard Fels; John P. Hardt; Marvin Hoffenberg; Norman Kaplan; Herbert S. Levine Econometrica 1970 38(5), 779