EXHIBIT A TO SCHEDULE 13G
                    ITEM 7 DISCLOSURE RESPECTING SUBSIDIARIES


RT Investment Management Holdings Inc, ("RTIM") is a parent holding company as
that term is defined by Rule 13d-1(b)(1)(ii)(G) of the Securities Exchange Act
of 1934 (the "Act") and is eligible to file on Schedule 13G pursuant to an SEC
no-action relief application. RTIM's aggregation holdings represent securities
that are beneficially owned by its subsidiaries which manage these securities on
behalf of their respective clients. RTIM's subsidiaries include, Royal Bank
Investment Management Inc., RT Capital Management Inc., and RBC Private Counsel
Inc.

Royal Bank Investment Management Inc. ("RBIM") is a wholly-owned subsidiary of
RTIM. RBIM is a foreign investment adviser that has received SEC no-action
relief to file on Schedule 13G.

RT Capital Management Inc. ("RT Capital") is a wholly-owned subsidiary of RTIM.
RT Capital is a foreign investment adviser that has received SEC no-action
relief to file on Schedule 13G.

RBC Private Counsel Inc. ("RPC") is a wholly-owned subsidiary of RTIM. RTIC is a
foreign investment adviser that has received SEC no-action relief to file on
Schedule 13G.

RTIM, RBIM, RT Capital and RPC are federally incorporated Canadian corporations
whose business addresses are as follows:

RT Investment Management                Royal Bank Investment
Holdings Inc.                           Management Inc.
Royal Trust Tower, P.O. Box 97          Royal Trust Tower, P.O. Box 97
77 King Street West, Suite 3900         77 King Street West, Suite 3800
Toronto, Ontario                        Toronto, Ontario
M5K 1G8                                 M5K 1G8

RT Capital Management Inc.              RBC Private Counsel Inc.
Royal Trust Tower, P.O. Box 97          Royal Trust Tower, P.O. Box 97
77 King Street West, Suite 3700         77 King Street West, Suite 3900
Toronto, Ontario                        Toronto, Ontario
M5K 1G8                                 M5K 1G8