The economy OWE used to be booked in M class, hence MONE, MHONE, MLONE (where H and L, are high and low season respectively).

Now the economy OWE are booked in L class, therefore the codes are LONE, LHONE and LLONE.

(edited to add: ExMo beat me to it)

[This message has been edited by Dani (edited Jan 21, 2004).]