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- [2] A SUFFICIENT CONDITION FOR THE EXISTENCE OF LIMIT-CYCLES OF CLASS(II) OF QUADRATIC SYSTEMS KEXUE TONGBAO, 1983, 28 (08): : 1139 - 1139
- [10] Cyclicity of common slow-fast cycles INDAGATIONES MATHEMATICAE-NEW SERIES, 2011, 22 (3-4): : 165 - 206