Erkki Mäkinen On pure context-free language and left szilard languages. [Citation Graph (0, 0)][DBLP] Fundam. Inform., 1991, v:15, n:1, pp:86-89 [Journal]
Juraj Hromkovic On the power of two-dimensional synchronized alternating finite automata. [Citation Graph (0, 0)][DBLP] Fundam. Inform., 1991, v:15, n:1, pp:90-98 [Journal]