1. V. V. Lenskil, ?Experimental verification of laws governing isotropy and lag under complex loading,? Izv. Akad. Nauk SSSR, Otd. Tekh. Nauk, No. 11, 15?24 (1958).
2. V. P. Degtyarev, ?Some methodological problems associated with failure criteria under a complex stressed state and complex loading,? Izv. Akad. Nauk SSSR, Mekh. Tverd. Tela, No. 1, 187?191 (1978).
3. Yu. I. Yagn and L. V. Grebnev, ?Effect of the rotation of the principal stress axes on the resistance of metals to plastic deformation and failure,? Tr. Leningr. Politekh. Inst.,278, 66?69 (1967).
4. A. M. Zhukov, ?Plastic deformations of steel under complex loading,? Izv. Akad. Nauk SSSR, Otd. Tekh. Nauk, No. 11, 53?61 (1954).
5. A. A. Il'yushin, ?On the relation between stresses and small strains in continuum mechanics,? Prikl. Mat. Mekh.,18, No. 6, 641?666 (1954).