11. Lenbury, Y., Rattanamongkonkul, S., Tumrasvin, N., and Amornsamankul, S. Predator-prey interaction coupled by parasitic infection: limit cycles and chaotic behavior.Mathl. Comput. Modelling. 30 (1999) 131-146.

12. Lenbury, Y., Tumrasvin, N. Singular perturbation analysis of a model for the effect of toxicant in single-species systems. Mathl. Comput. Modelling. 31 (2000) 125-134.

13. Lenbury, Y., Ouncharoen, R., and Tumrasvin, N. Higher dimensional separation principle for the analysis of relaxation oscillations in nonlinear systems: application to a model of HIV infection. IMA Journal of Mathematics Applied in Medicine and Biology. 17 (2000) 243-261.

14. Lenbury, Y., Pansuwan, A., and Tumrasvin, N. Chaos and control action in a kolmogorov type model for food webs with harvesting or replenishment. ScienceAsia. 28(3) (2002) 205-215.