1. 1
    Published 1989
    ...HC 661 .L434...
    Journal
  2. 2
    Published 1993
    ...HC 621 .N532 n...
    Journal
  3. 3
    Published 1988
    ...HC 621 .N532 n...
    Journal
  4. 4
    Published 2002
    ...HD 62.7 .S6354...
    Journal
  5. 5
    Published 1995
    ...HC 621 .N532 n...
    Journal