MARC21       007h'04  Dimensions
     Values: 
             Microfilm
             a   8 mm.
              a   8 mm.
              d   16 mm.
              f   35 mm.
              g   70 mm.
              h   105 mm.
                  Microfiche and Microopaque
              l   3x5 in. or 8x13 cm.
              m   4x6 in. or 11x15 cm.
              o   6x9 in. or 16x23 cm.
                  Aperture cards
              p   3 1/4 x 7 3/8 in. or 9x19 cm.
              u   Unknown
              z   Other