Ashwin, P.; Buescu, J.; Stewart, I. (1996). “From attractor to chaotic saddle: A tale of transverse instability”. Nonlinearity9 (3): 703. doi:10.1088/0951-7715/9/3/006.
Collins, J. J.; Stewart, I. N. (1993). “Coupled nonlinear oscillators and the symmetries of animal gaits”. Journal of Nonlinear Science3: 349. doi:10.1007/BF02429870.
“STEWART, Prof. Ian Nicholas”. Who's Who 2014, A & C Black, an imprint of Bloomsbury Publishing plc, 2014; online edn, Oxford University Press. 2018年2月15日閲覧。(要購読契約)