Normal L-fuzzy ideals in semirings. - Young Bae Jun; Joseph Neggers; Hee Sik Kim (Fuzzy Sets Syst., 1996)

Fuzzy implicative ideals of BCK-algebras. - Jie Meng; Young Bae Jun; Hee Sik Kim (Fuzzy Sets Syst., 1997)

Connections Between BCK-algebras and Difference Posetse. - Anatolij Dvurecenskij; Hee Sik Kim (Stud Logica, 1998)

Fuzzy subinclines (ideals) of incline algebras. - Young Bae Jun; Sun Shin Ahn; Hee Sik Kim (Fuzzy Sets Syst., 2001)

Quotient structures of some implicative algebras via fuzzy implicative filters. - Young Bae Jun; Sun Shin Ahn; Hee Sik Kim (Fuzzy Sets Syst., 2001)

Fuzzy posets on sets. - Joseph Neggers; Hee Sik Kim (Fuzzy Sets Syst., 2001)

Special classes of positive implication algebras. - Young Bae Jun; Hee Sik Kim; Sun Shin Ahn (Inf. Sci., 2003)

Fuzzy pogroupoids. - Hee Sik Kim; Joseph Neggers (Inf. Sci., 2005)

Intuitionistic Fuzzy Approach to Topological BCK-Algebras. - Young Bae Jun; Hee Sik Kim (J. Multiple Valued Log. Soft Comput., 2006)

On pseudo-fuzzy linear mappings. - Hee Sik Kim; B. Monk; Joseph Neggers (Inf. Sci., 2007)

Fibonacci mean and golden section mean. - Hee Sik Kim; Joseph Neggers (Comput. Math. Appl., 2008)

Representation functions and the Neggers-Stanley condition for weight-shaped-posets. - Keumseong Bang; Hee Sik Kim; Joseph Neggers (Comput. Math. Appl., 2009)

Pseudo d-algebras. - Young Bae Jun; Hee Sik Kim; Joseph Neggers (Inf. Sci., 2009)

Fuzzy structures of hyper-MV-deductive systems in hyper-MV-algebras. - Young Bae Jun; Min Su Kang; Hee Sik Kim (Comput. Math. Appl., 2010)

New types of hyper MV-deductive systems in hyper MV-algebras. - Young Bae Jun; Min Su Kang; Hee Sik Kim (Math. Log. Q., 2010)

Strong and Ordinary d-Algebras. - Jeong Soon Han; Hee Sik Kim; Joseph Neggers (J. Multiple Valued Log. Soft Comput., 2010)

Trends, probability functions and fuzzy right ideals for d-algebras. - Kyung Joon Cha; Hee Sik Kim; Joseph Neggers (Comput. Math. Appl., 2011)

BCK-Algebras and Related Algebraic Systems. - Young Bae Jun; Ivan Chajda; Hee Sik Kim; Eun Hwan Roh; Jianming Zhan 001; Afrodita Iorgulescu (Int. J. Math. Math. Sci., 2011)

The Hypergroupoid Semigroups as Generalizations of the Groupoid Semigroups. - Jeong Soon Han; Hee Sik Kim; Joseph Neggers (J. Appl. Math., 2012)

Further Results on Derivations of Ranked Bigroupoids. - Young Bae Jun; Hee Sik Kim; Eun Hwan Roh (J. Appl. Math., 2012)

Some Aspects of d-Units in d/BCK-Algebras. - Hee Sik Kim; Joseph Neggers; Keum Sook So (J. Appl. Math., 2012)

On linear fuzzifications of groupoids with special emphasis on BCK-algebras. - Jeong Soon Han; Hee Sik Kim; Joseph Neggers (J. Intell. Fuzzy Syst., 2013)

On the fuzzy polynomial ideals. - Chang Bum Kim; Hee Sik Kim; Keum Sook So (J. Intell. Fuzzy Syst., 2014)

Some types of falling fuzzy filters of BL-algebras and its applications. - Jianming Zhan 001; Young Bae Jun; Hee Sik Kim (J. Intell. Fuzzy Syst., 2014)

Non-commutative residuated lattices based on soft sets. - Yong Lin Liu; Hee Sik Kim (J. Intell. Fuzzy Syst., 2015)

Hyperfuzzy subsets and subgroupoids. - Yong Lin Liu; Hee Sik Kim; Joseph Neggers (J. Intell. Fuzzy Syst., 2017)

Hesitant fuzzy translations and extensions of subalgebras and ideals in BCK/BCI-algebras. - G. Muhiuddin; Hee Sik Kim; Seok-Zun Song; Young Bae Jun (J. Intell. Fuzzy Syst., 2017)

A New Type of Subsemigroups and Ideals of Semigroups in the Framework of Hesitant Fuzzy Set Theory. - Young Bae Jun; Hee Sik Kim; Seok-Zun Song (J. Multiple Valued Log. Soft Comput., 2017)

A Method to Identify Simple Graphs by Special Binary Systems. - Hee Sik Kim; Joseph Neggers; Sun Shin Ahn (Symmetry, 2018)

Constructing (pre)norms in BL-algebras and its action on topological BL-algebras. - Rajab Ali Borzooei; Hee Sik Kim; Nader Kouhestani (J. Intell. Fuzzy Syst., 2019)

Almost φ-fuzzy semi-ideals in groupoids. - Hee Sik Kim; Joseph Neggers; Sun Shin Ahn (J. Intell. Fuzzy Syst., 2019)

Fuzzy Subgroups and Digraphs Induced by Fuzzy Subgroups. - Paul J. Allen; Joseph Neggers; Hee Sik Kim (TFSS, 2022)

On BE-ringoids. - Akbar Rezaei; S. Borhani Nejad Rayeni; Hee Sik Kim (Soft Comput., 2023)

Some Orders in Groupoids and Its Applications to Fuzzy Groupoids. - Akbar Rezaei; Choonkil Park; Hee Sik Kim (TFSS, 2025)