Finite-state transducers were introduced by Sheperdson (1959). Deterministic finite-state automata originated in McCulloch and Pitts (1943). Rabin and Scott (1959) introduced nondeterminism to finite-state automata, and showed the equivalency of nondeterministic finite-state automata to deterministic finite-state automata. The representation of finite-state transducers by transition diagrams is due to Myhill (1957).
Chomsky and Miller (1958) showed the equivalency of the class of languages accepted by finite-state automata and the class of Type 3 languages. Kleene (1956) showed that the languages that finite-state automata accept are characterized by regular expressions. LEX is due to Lesk (1975).
The pumping lemma for regular languages is due to Bar-Hillel , Perles , and Shamir (1961). Beauquier (see Ehrenfeucht , Parikh , and Rozenberg , 1981) showed the existence of a nonregular language that certifies the conditions of the pumping lemma.
The decidability of the emptiness and equivalence problems for finite-state automata, as well as Exercise 2.6.1, have been shown by Moore (1956).
Hopcroft and Ullman (1979) is a good source for additional coverage of these topics.