Burke, J. V. 1991. Calmness and exact penalization. SIAM Journal on Control and Optimization. 29 493–497.

Burke, J. V. 1991. An exact penalization viewpoint of constrained optimization. SIAM Journal on Control and Optimization. 29 968–998.

Cominetti, R., R. Correa. 1990. A generalized second-order derivative in nonsmooth optimization. SIAM Journal on Control and Optimization. 28 789–809.

W. L. Chan;L. R. Huang and K. F. Ng. 1994. On Generalized Second-Order Derivatives and Taylor Expansions in Nonsmooth Optimization.SIAM Journal on Control and Optimization. No.3  Vol.32. 591-611.