1.2.89. card68

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C68 INITIAL DRIFTER POSITIONS (FOR USE WITH SUB DRIFTER)
*
*  RI: I CELL INDEX IN WHICH PARTICLE IS RELEASED IN
*  RJ: J CELL INDEX IN WHICH PARTICLE IS RELEASED IN
*  RK: K CELL INDEX IN WHICH PARTICLE IS RELEASED IN
*
C68      RI      RJ      RK