M. Margenstern et L. Pavlotskaia, 2 UNIVERSAL TURING-MACHINES WITH AT MOST 2 LEFT INSTRUCTIONS, Comptes rendus de l'Academie des sciences. Serie 1, Mathematique, 320(11), 1995, pp. 1395-1400
A universal Turing machine is constructed on alphabet {0, 1}, the prog
ram of which contains precisely two instructions involving left moves.
Another one is constructed on {0, 1, 2} with a single instruction inv
olving a left move.