The type of parenthesis used in citations may be set using the
\harvardparenthesis
command which takes one argument.
The argument to this command must be one of
round, curly, angle or square.
The default value is round.
If the bibliographic style chosen is agsm or dcu then the parenthesis
style chosen using
\harvardyearparenthesis is used with the
year portion of the entries in the bibliographic listing.
Authors of style files for use with the harvard family who wish to make
use of this feature should use the strings " \harvardleft " and
" \harvardright " instead of the respective parenthesis characters where
they wish them to be effected by the selection made with
\harvardparenthesis.