As others have written, sadly there is no famous M. Litre.
An interesting point about this unit is that like all those
units such as the metre, gram, second etc, which are not
named after scientists, it really should have a lower-case l
in its abbreviated state. A lower-case l is very hard to
distinguish from the integer 1. As I remember, for some
time an attempt to get round this problem was made by using
a script l, but that wasn't very successful. Finally, the
upper-case L was used, which left it open to develop little
jokes about the mysterious M. Litre
Brian McInnes