C Collection of code snippets by Arne Vajhøj 
C (from articles on eksperten.dk / vajhoej.dk written sometime between 2004 and now) 
      PROGRAM COMM
      INTEGER*4 I,J,K
      COMMON /B1/I
      COMMON /B2/J
      COMMON /B3/K
      I=123
      J=456
      K=65537
      CALL SUB1
      CALL SUB2
      CALL SUB3
      END
C
      SUBROUTINE SUB1
      INTEGER*4 I
      COMMON /B1/I
      WRITE(*,*) I
      RETURN
      END
C
      SUBROUTINE SUB2
      INTEGER*4 J
      COMMON /B2/J
      WRITE(*,*) J
      RETURN
      END
C
      SUBROUTINE SUB3
      INTEGER*2 K1,K2
      COMMON /B3/K1,K2
      WRITE(*,*) K1,K2
      RETURN
      END