1. H. H. Mitchell, The subgroups of the quaternary abelian linear groups, Trans. Amer. Math. Soc., 1911, 12
2. L. E. Dickson, Canonical forms of quaternary abelian substitutions in an arbitrary Galois field, Trans, Amer. Math. Soc., 1901, 2:103–138
3. D. Flesner, Maximal subgroups of the 4-dimensional symplectic groups in characteristic two, Ph. D. Thesis, University of Michigan, 1971
4. M. I. Alali, On the characters of the maximal subgroups of the projective symplectic group PSP 4(q) − q odd prime, Ph. D. thesis, University of Birmingham, 1987
5. B. Srinivasan, The characters of the finite symplectic group SP 4( q), Trans. Amer. Math. Soc., 1986, 131:488–525