2[1]Hartvani I. On the partial stability of ordinary differential equation (in Russian)[J]. Venik Moscow Univ Math Mech,1975;3:83-89
3[2]Vorotnikov V. On stability and stabilization motion with respect to some variables for linear delayed systems[J]. Automata and Telemechanics (in Russian),1980;8:36-47
4[3]Vorotnikov V. The partial stability of dynamic systems[M]. Moscow(Science),1991
5[5]Hartvani L. Applied math[J]. and Mechanic(in Russian),1976;40(2):245-251