"Tiling systems"@en . "Dora" . . "Two-dimensional language"@en . "Unambiguity"@en . "Prefix codes"@en . "Overlap"@en . "Measure"@en . "Two-dimensional languages"@en . "Determinism"@en . "Unbordered picture"@en . "Dora Giammarresi" . "Giammarresi" . "04a669c20878feb9c07297c5cb80bad0" . . "Automata and formal languages"@en .