@incollection{SB_1978-1979__21__228_0,
     author = {Bertrand, Daniel},
     title = {Travaux r\'ecents sur les points singuliers des \'equations diff\'erentielles lin\'eaires},
     booktitle = {S\'eminaire Bourbaki : vol. 1978/79, expos\'es 525-542},
     series = {S\'eminaire Bourbaki},
     note = {talk:538},
     pages = {228--243},
     publisher = {Springer-Verlag},
     number = {21},
     year = {1980},
     mrnumber = {572427},
     zbl = {0445.12012},
     language = {fr},
     url = {http://www.numdam.org/item/SB_1978-1979__21__228_0/}
}