k-z kkk kkm kkr kmk kmm kmo kmz kok kom koo kor koz krk kro krr kzo m-o m-r mkk mkm mko mkr mkz mmk mmm mmo mmr mmz mok mom moo mor moz mrk mrm mro mrr mrz mzm okk oko okr om- omm omo omr omz oo- ook oom ooo oor or- ork orm oro orr orz ozm ozo ozz rkk rkm rko rkz rmm rmo rmr rok rom roo ror roz rrk rrm rrr rzm rzo zmk zmm zo- zok zom zoo zor zro zzr zzz