[1] G. Birkhoff: Lattice Theory. Am. Math. Soc. Coll. Publ. XXV. Sec. Ed. 1948. Zbl 0033.10103

[2] K. Gödel: Die Vollständigkeit der Axiome des logischen Funktionenkalküls. Mh. Math. Ph. 37 (1930).

[3] D. Hilbert W. Ackermann: Grundzüge der theoretischen Logik. Grundl. d. math. Wiss. XXVII Springer, Zw. A. 1938.

[4] D. Hilbert P. Bernays: Grundlagen der Mathematik. Bd. II, Springer 1939.

[5] L. Henkin: A proof of completeness for the first order functional calculus. J. Symb. L. 14, (1949), 159-166. DOI 10.2307/2267044 | MR 0033781

[6] H. L. Loomis: On the representation of $\sigma$-complete Boolean algebras. Bull. Am. Math. Soc. 53 (1947), 757-760. DOI 10.1090/S0002-9904-1947-08866-2 | MR 0021084 | Zbl 0033.01103

[7] H. Mac Neille: Extensions of partially ordered sets. Proc. Nat. Ac. USA, 22 (1936), 45-50. DOI 10.1073/pnas.22.1.45

[8] A. Mostowski: Logika matematyczna. Monografie mat., Warszawa, 1948. MR 0026972

[9] A. Mostowski: Abzählbare Boolesche Körper und ihre Anwendung in der Metamathematik. Fund. Math. 29 (1937), 34-53.

[10] L. Rieger: On $\aleph\sb \xi$-complete free Boolean Algebras. (With an application to logic.) (To appear in Fund. Math. 1951.) MR 0050561

[11] R. Sikorski: On the representation of Boolean algebras as fields of sets. Fund. Math. 35 (1948), 247-258. DOI 10.4064/fm-35-1-247-258 | MR 0028374 | Zbl 0035.01704