[1] W. Bruns and J. Herzog, Cohen-Macaulay rings, Cambridge University Press, Cambridge, UK, (1998).
[2] H. Matsumura, Commutative ring theory, Cambridge University Press, Cambridge, UK, (1986).
[3] A. Ooishi, Matlis duality and width of a module, Hiroshima Math. J., 6 (1976), 573-587.