A non-implication between fragments of Martin's Axiom related to a property which comes from Aronszajn trees (vol 4, pg 469, 2010)

作者：Yorioka Teruyuki^*

来源：Annals of Pure and Applied Logic, 2011, 162(9): 752-754.

DOI：10.1016/j.apal.2011.02.003

• Martin's Axiom and its fragments
• Non-special Aronszajn trees

In the paper A non-implication between fragments of Martin's Axiom related to a property which comes from Aronszajn trees (Yorioka, 2010 (11), Proposition 2.7 is not true. To avoid this error and correct Proposition 2.7, the definition of the property R(1),(delta 1) is changed. In Yorioka (2010) 111, all proofs of lemmas and theorems but Lemma 6.9 are valid about this definition without changing the proofs. We give a new statement and a new proof of Lemma 6.9.