Algebraic disguises ofΣ10 induction. - Kostas Hatzikiriakou (Arch. Math. Log., 1989)

Countable Valued Fields in Weak Subsystems of Second-Order Arithmetic. - Kostas Hatzikiriakou; Stephen G. Simpson (Ann. Pure Appl. Log., 1989)

Minimal Prime Ideals and Arithmetic Comprehension. - Kostas Hatzikiriakou (J. Symb. Log., 1991)

A note on ordinal numbers and rings of formal power series. - Kostas Hatzikiriakou (Arch. Math. Log., 1994)

WKL0 and Stone's Separation Theorem for Convex Sets. - Kostas Hatzikiriakou (Ann. Pure Appl. Log., 1996)

Reverse Mathematics, Young Diagrams, and the ascending Chain condition. - Kostas Hatzikiriakou; Stephen G. Simpson (J. Symb. Log., 2017)