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                                                                     EXHIBIT 3.1


                          CERTIFICATE OF INCORPORATION

                                       OF

                          PLD CAPITAL ASSET (U.S.) INC.

                  The undersigned incorporator, for the purpose of incorporating
or organizing a corporation under the General Corporation Law of the State of
Delaware, certifies:

                  FIRST:  The name of the corporation is
                          PLD Capital Asset (U.S.) Inc.

                  SECOND: The address of the Corporation's registered office in
the State of Delaware is 30 Old Rudnick Lane, Suite 100, in the City of Dover,
County of Kent. The name of its registered agent at such address is LEXIS
Document Services Inc.

                  THIRD: The purpose of the Corporation is to engage in any
lawful act or activity for which corporations may be organized under the General
Corporation Law of Delaware.

                  FOURTH: The total number of shares of stock which the
Corporation shall have authority to issue is One Thousand (1,000) shares of
Common Stock, and the par value of each such share is One Cent ($0.01).
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                  FIFTH: The name and mailing address of the incorporator is H.
Franklin Bloomer, Jr., Morgan, Lewis & Bockius LLP, 101 Park Avenue, New York,
New York 10178.

                  SIXTH: Elections of directors need not be by ballot unless the
By-Laws of the Corporation shall so provide.

                  SEVENTH: The Board of Directors of the Corporation may make
By-Laws and from time to time may alter, amend or repeal By-Laws.

                  EIGHTH: No director of the Corporation shall be liable to the
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a director, except for liability (i) for any breach of the director's
duty of loyalty to the Corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the Delaware General Corporation
Law, or (iv) for any transaction from which the director derived an improper
personal benefit.

                  NINTH: Whenever a compromise or arrangement is proposed
between this Corporation and its creditors or any class of them and/or between
this Corporation and its stockholders or any class of them, any court of
equitable jurisdiction within the State of Delaware may, on the application in a
summary way of this Corporation or of any creditor or stockholder thereof or on
the application of any receiver or receivers appointed for this Corporation
under the provisions of section 291 of Title 8 of the Delaware Code or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this Corporation under the provisions of
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section 279 of Title 8 of the Delaware Code order a meeting of the creditors or
class of creditors, and/or of the stockholders or class of stockholders of this
Corporation, as the case may be, to be summoned in such manner as the said court
directs. If a majority in number representing three-fourths in value of the
creditors or class of creditors, and/or of the stockholders or class of
stockholders of this Corporation, as the case may be, agree to any compromise or
arrangement and to any reorganization of this Corporation as consequence of such
compromise or arrangement, the said compromise or arrangement and the said
reorganization shall, if sanctioned by the court to which the said application
has been made, be binding on all the creditors or class of creditors, and/or on
all the stockholders or class of stockholders, of this Corporation, as the case
may be, and also on this Corporation.

                  IN WITNESS WHEREOF, I have signed this Certificate this 24th
day of March, 1998.

                                                     /s/ H. Franklin Bloomer
                                                     H. Franklin Bloomer, Jr.