1. J. Willard Gibbs,Elementary Principles of Statistical Mechanics (Yale University Press, New Haven, 1902).
2. D. Kastler,Equilibrium States of Matter and Operator Algebras, Istituto Nazionale di Alta Matematica Symposia Matematica, vol. XX (Rome, 1976).
3. W. Pusz and S. L. Woronowicz,Comm. Math. Phys. 58:273 (1978).
4. L. Mirsky,Transversal Theory (Academic Press, New York, 1971), Section 11.3.
5. Theorem 368;G. H. Hardy,1934