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On categorial and phrase-structure grammars. Bull. Res. Counc. of Israel, Vol. 9F, 1960.
MR 0136014 |
Zbl 0158.25306
[2] Burris S., Sankappanavar H. P.:
A course to universal algebra. Springer-Verlag, New York, 1981.
MR 0648287