@article{JLT_2002_12_1_JLT_2002_12_1_a11, author = {E. G. F. Thomas }, title = {An {Invariant} {Symmetric} {Non-Selfadjoint} {Differential} {Operator}}, journal = {Journal of Lie theory}, pages = {245--257}, publisher = {mathdoc}, volume = {12}, number = {1}, year = {2002}, url = {http://geodesic.mathdoc.fr/item/JLT_2002_12_1_JLT_2002_12_1_a11/} }