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EXHIBIT 3
POWER OF ATTORNEY
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Know all men by these presents that each of Richard F. Hoskins and Richard
D. Paterson does hereby make, constitute and appoint Jean-Pierre L. Conte as a
true and lawful attorney-in-fact of the undersigned with full powers of
substitution and revocation, for and in the name, place and stead of the
undersigned, (both in the undersigned's individual capacity and as a member of
any limited liability company or partner of any partnership for which the
undersigned is otherwise authorized to sign), to execute and deliver such forms
as may be required to be filed from time to time with the Securities and
Exchange Commission with respect to any investments of Genstar Capital LLC,
Genstar Capital Partners II, L.P. and Stargen II LLC or the undersigned
(including any amendments or supplements to any reports from schedules
previously filed by such persons or entities) including any joint filing
agreements or joint filer information statements in connection therewith with
respect to BioSource International, Inc.: (i) pursuant to Sections 13(d) and
16(a) of the Securities Exchange Act of 1934, as amended, including without
limitation, Schedules 13D and 13G, statements on Form 3, Form 4 and Form 5 and
(ii) in connection with any applications for EDGAR access codes, including
without limitation the Form ID.
/s/ Richard F. Hoskins
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Name: Richard F. Hoskins
/s/ Richard D. Paterson
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Name: Richard D. Paterson
Dated: October 6, 2000
