6 papers:
LICS-2013-Otto #finite #modelling #symmetry- Groupoids, Hypergraphs, and Symmetries in Finite Models (MO), pp. 53–62.
LATA-2012-DubeLT #regular expression- Conservative Groupoids Recognize Only Regular Languages (DD, ML, PT), pp. 216–227.
CSL-2012-AltenkirchR #approach- A Syntactical Approach to Weak ω-Groupoids (TA, OR), pp. 16–30.
ICALP-2005-BeaudryLT #regular expression- Groupoids That Recognize Only Regular Languages (MB, FL, DT), pp. 421–433.
LICS-1994-HofmannS #proving- The Groupoid Model Refutes Uniqueness of Identity Proofs (MH, TS), pp. 208–212.
CSL-1987-GermanoM #category theory #diagrams- Loose Diagrams, Semigroupoids, Categories, Groupoids and Iteration (GG, SM), pp. 64–80.