@article{01669814, title = {Testing block sphericity of a covariance matrix.}, journal = {Divulgaciones Matem\'aticas}, volume = {9}, year = {2001}, pages = {25-34}, zbl = {0988.62032}, language = {en}, url = {http://dml.mathdoc.fr/item/01669814} }
Cardeño, Liliam; Nagar, Daya K. Testing block sphericity of a covariance matrix.. Divulgaciones Matemáticas, Tome 9 (2001) pp. 25-34. http://gdmltest.u-ga.fr/item/01669814/