References
- Canad. J. Math. v.52 The homotopy set of the axes of pairings Oda, N.
- Amer. J. Math. v.87 A certain subgroup of the fundamental group Gottlieb, D.H.
- Amer. J. Math. v.91 Evaluation subgroup of homotopy groups Gottlieb, D.H.
- J. Indian Math. Soc. v.33 Generalized Gottlieb groups Varadarajan, K.