@article{GDZPPN002219158, title = {Constants Related to Operators of Class Cp.}, journal = {Manuscripta mathematica}, volume = {17}, year = {1975}, pages = {385-394}, zbl = {0325.47008}, url = {http://dml.mathdoc.fr/item/GDZPPN002219158} }
Ando, T.; Okubo, K. Constants Related to Operators of Class Cp.. Manuscripta mathematica, Tome 17 (1975) pp. 385-394. http://gdmltest.u-ga.fr/item/GDZPPN002219158/