A generalized Ogden's lema for linear conteext-free languages. - Rattikorn Boonyavatana; Giora Slutzki (Bull. EATCS, 1986)

Ogden's Lemma for Nonterminal Bounded Languages. - Rattikorn Boonyavatana; Giora Slutzki (RAIRO Theor. Informatics Appl., 1986)

Note: on the sufficiency of Igarashi's conditions for real-time deterministic context-free-languages. - Rattikorn Boonyavatana; Giora Slutzki (Bull. EATCS, 1987)

The Interchange or Pump (Di)Lemmas for Context-Free Languages. - Rattikorn Boonyavatana; Giora Slutzki (Theor. Comput. Sci., 1988)