Graham Ellis. The Schur Multiplier of a Pair of Groups. Applied Categorical Structures, 6(3):355-371, 1998. [doi]
@article{Ellis98-1, title = {The Schur Multiplier of a Pair of Groups}, author = {Graham Ellis}, year = {1998}, doi = {10.1023/A:1008652316165}, url = {http://dx.doi.org/10.1023/A:1008652316165}, researchr = {https://researchr.org/publication/Ellis98-1}, cites = {0}, citedby = {0}, journal = {Applied Categorical Structures}, volume = {6}, number = {3}, pages = {355-371}, }