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                                                                  Exhibit 3.xiii
FILED
in the office of the
Secretary of State of the
STATE OF NEVADA
DEC 11 1998
No. C3947-85
/s/ Dean Heller
Dean Heller, Secretary of State


                            CERTIFICATE OF AMENDMENT

                                       TO

                            ARTICLES OF INCORPORATION

                                       OF

                       TERRA NATURAL RESOURCES CORPORATION
                             (dba NEVADA MANHATTAN)


         We  the  undersigned  as  President  and  Secretary  of  Terra  Natural
Resources  Corporation (dba Nevada Manhattan),  do hereby certify:  (i) That the
Board of Directors of said  corporation  at a meeting duly  convened and held on
the 3rd day of  September,  1998,  adopted a resolution to amend the Articles of
Incorporation as follows:


                  Article I shall be amended to read as follows:

         "The name of the corporation TERRA NATURAL  RESOURCES  CORPORATION (dba
NEVADA  MANHATTAN),  shall be changed to the corporate name of NEVADA  MANHATTAN
GROUP, INCORPORATED."

                                    (ii)  That the  Board of  Directors  of said
corporation at a meeting duly convened and held on the 30th day of August, 1998,
adopted  a  resolution  to amend  the  Articles  of Incorporation as follows:


                  Article V is amended to read in its entirety as follows:

                                   "ARTICLE V

         This  corporation  is  authorized  to issue two  classes of stock to be
designated, respectively, 'Common Stock' and 'Preferred Stock.' The total number
of shares which the corporation is authorized to issue is 250,250,000 shares, of
which 250,000,000 shares shall be Common Stock, par value of $.01 per share, and
250,000  shares  shall be  Preferred  Stock,  par value of $1.00 per share.  The
Preferred Stock may be issued from time to time in one or more series. The Board
of  Directors  is  authorized  to fix the  number  of  shares  of any  series of
Preferred  Stock and to  determine  or alter the  voting  rights,  designations,
preferences, limitations, restrictions and relative rights granted to or imposed
upon any wholly  unissued  series of Preferred  Stock and, within the limits and
restrictions  stated in any  resolution or resolutions of the Board of Directors
originally  fixing the number of shares  constituting any series, to increase or
decrease  (but not below the number of shares of such series  then  outstanding)
the number of shares of any such  series  subsequent  to the issues of shares of
that series."

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         The said changes and amendments  have been consented to and approved by
a majority  of the  stockholders  holding  each class of stock  outstanding  and
entitled  to vote  thereon at an annual  stockholders  meeting of Terra  Natural
Resources Corporation held on December 9, 1998; that the number of shares of the
corporation  outstanding  and entitled to vote on  amendments to the Articles of
Incorporation  was  forty-one  million,  seven hundred  forty-two  thousand four
hundred seventy-seven (41,742,477) shares, one cent par value.


                                             /s/ Christopher D. Michaels
                                            -----------------------------------
                                            CHRISTOPHER D. MICHAELS, President

                                             /s/ Jeffrey S. Kramer
                                            ------------------------------------
                                            JEFFREY S. KRAMER, Secretary