Pw{ cal P}_w Is Not a Heyting Algebra. - Kojiro Higuchi (CiE, 2010)

The degree structure of Weihrauch-reducibility - Kojiro Higuchi; Arno Pauly (Log. Methods Comput. Sci., 2011)

Effective Strong Nullness and Effectively Closed Sets. - Kojiro Higuchi; Takayuki Kihara (CiE, 2012)

Relative Randomness for Martin-Löf Random Sets. - NingNing Peng; Kojiro Higuchi; Takeshi Yamazaki; Kazuyuki Tanaka (CiE, 2012)

Effectively closed mass problems and intuitionism. - Kojiro Higuchi (Ann. Pure Appl. Log., 2012)

Inside the Muchnik Degrees: Discontinuity, Learnability, and Constructivism - Kojiro Higuchi; Takayuki Kihara (CoRR, 2012)

Weak theories of concatenation and minimal essentially undecidable theories - An encounter of $${ mathsf{WTC}}$$ WTC and $${ mathsf{S2S}}$$ S 2 S. - Kojiro Higuchi; Yoshihiro Horihata (Arch. Math. Log., 2014)

Propagation of partial randomness. - Kojiro Higuchi; W. M. Phillip Hudelson; Stephen G. Simpson; Keita Yokoyama (Ann. Pure Appl. Log., 2014)

Inside the Muchnik degrees I: Discontinuity, learnability and constructivism. - Kojiro Higuchi; Takayuki Kihara (Ann. Pure Appl. Log., 2014)

Inside the Muchnik degrees II: The degree structures induced by the arithmetical hierarchy of countably continuous functions. - Kojiro Higuchi; Takayuki Kihara (Ann. Pure Appl. Log., 2014)

On effectively closed sets of effective strong measure zero. - Kojiro Higuchi; Takayuki Kihara (Ann. Pure Appl. Log., 2014)

On the strength of marriage theorems and uniformity. - Makoto Fujiwara; Kojiro Higuchi; Takayuki Kihara (Math. Log. Q., 2014)

Defining a randomness notion via another. - Kojiro Higuchi; NingNing Peng (Math. Log. Q., 2014)