ACM Transactions on Computational Logic, 23(4):22, 1-56. Association for Computing Machinery (ACM) ACM Transactions on Computational Logic, 23(4):22. Association for Computing Machinery, Inc Aceto, L, Castiglioni, V, Fokkink, W, Ingólfsdóttir, A & Luttik, B 2022, ' Are Two Binary Operators Necessary to Obtain a Finite Axiomatisation of Parallel Composition? ', ACM Transactions on Computational Logic, vol. 23, no. 4, 22, pp. 1-56 . https://doi.org/10.1145/3529535