- Edmond W. H. Lee, “On Certain Cross Varieties of Aperiodic Monoids with Commuting Idempotents”, Results. Math., 66, № 3-4, 2014, 491
![https://doi.org/10.1007/s00025-014-0390-6 crossref](/refsvg/svg/crossref.svg)
- Edmond W. H. Lee, Advances in the Theory of Varieties of Semigroups, 2023, 227
![https://doi.org/10.1007/978-3-031-16497-2_12 crossref](/refsvg/svg/crossref.svg)
- Edmond W. H. Lee, “Almost Cross varieties of aperiodic monoids with central idempotents”, Beitr Algebra Geom, 54, № 1, 2013, 121
![https://doi.org/10.1007/s13366-012-0094-6 crossref](/refsvg/svg/crossref.svg)
- E. W. H. Lee, “Inherently Non-Finitely Generated Varieties of Aperiodic Monoids with Central Idempotents”, J Math Sci, 209, № 4, 2015, 588
![https://doi.org/10.1007/s10958-015-2515-1 crossref](/refsvg/svg/crossref.svg)