Classical proof forestry. - Willem Heijltjes (Ann. Pure Appl. Log., 2010)

Proof Nets for Additive Linear Logic with Units. - Willem Heijltjes (LICS, 2011)

Atomic Lambda Calculus: A Typed Lambda-Calculus with Explicit Sharing. - Tom Gundersen; Willem Heijltjes; Michel Parigot (LICS, 2013)

A Proof of Strong Normalisation of the Typed Atomic Lambda-Calculus. - Tom Gundersen; Willem Heijltjes; Michel Parigot (LPAR, 2013)

No proof nets for MLL with units: proof equivalence in MLL is PSPACE-complete. - Willem Heijltjes; Robin Houston (CSL-LICS, 2014)

Complexity Bounds for Sum-Product Logic via Additive Proof Nets and Petri Nets. - Willem Heijltjes; Dominic J. D. Hughes (LICS, 2015)

Conflict nets: Efficient locally canonical MALL proof nets. - Dominic J. D. Hughes; Willem Heijltjes (LICS, 2016)

Proof equivalence in MLL is PSPACE-complete. - Willem Heijltjes; Robin Houston (Log. Methods Comput. Sci., 2016)

Proof nets and semi-star-autonomous categories. - Willem Heijltjes; Lutz Straßburger (Math. Struct. Comput. Sci., 2016)

Proof Nets for Bi-Intuitionistic Linear Logic. - Gianluigi Bellin; Willem Heijltjes (FSCD, 2018)

Teaching of Computing to Mathematics Students: Programming and Discrete Mathematics. - Jack D. Betteridge; James H. Davenport; Melina A. Freitag; Willem Heijltjes; Stef Kynaston; Gregory Sankaran; Gunnar Traustason (CEP, 2019)

Intuitionistic proofs without syntax. - Willem B. Heijltjes; Dominic J. D. Hughes; Lutz Straßburger (LICS, 2019)

Proof Nets for First-Order Additive Linear Logic. - Willem Heijltjes; Dominic J. D. Hughes; Lutz Straßburger (FSCD, 2019)

Decomposing Probabilistic Lambda-Calculi. - Ugo Dal Lago; Giulio Guerrieri; Willem Heijltjes (FoSSaCS, 2020)

Spinal Atomic Lambda-Calculus. - David Sherratt; Willem Heijltjes; Tom Gundersen; Michel Parigot (FoSSaCS, 2020)

A Deep Quantitative Type System. - Giulio Guerrieri; Willem B. Heijltjes; Joseph W. N. Paulus (CSL, 2021)

Normalization Without Syntax. - Willem B. Heijltjes; Dominic J. D. Hughes; Lutz Straßburger (FSCD, 2022)

The Functional Machine Calculus. - Willem Heijltjes (MFPS, 2022)

The Functional Machine Calculus II: Semantics. - Chris Barrett; Willem Heijltjes; Guy McCusker (CSL, 2023)

The Relational Machine Calculus. - Chris Barrett; Daniel Castle; Willem Heijltjes (LICS, 2024)

The Functional Machine Calculus III: Choice (Early Announcement). - Willem Heijltjes (CoRR, 2024)

Simple Types for Probabilistic Termination. - Willem Heijltjes; Georgina Majury (CSL, 2025)

Quantitative Types for the Functional Machine Calculus. - Willem Heijltjes (FSCD, 2025)