P 3 C 1,NR.158*MJ*
LATT    -1
SYMM    -Y,   X-Y,     Z
SYMM   Y-X,    -X,     Z
SYMM    -Y,    -X, .5+Z
SYMM     X,   X-Y, .5+Z
SYMM   Y-X,     Y, .5+Z  
    0 .6666 / 0 .6666 / 0 .5
    SONDER: X .LE. (1+Y)/2
    SONDER: Y .LE. MIN. (1-X,(1+X)/2)
    P 3 C 1,NR.158*MJ*