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                                                                    EXHIBIT 10.1
                                    ADDENDUM



This Document represents an Addendum to that certain Application Service
Provider and Outsourcing Agreement made and entered into as of June 1, 2000 (the
"Effective Date") by and between Applied Terravision Systems Inc. predecessor to
CGI Information Systems & Management Systems, Inc., a Delaware corporation
("CGI") and Range Resources Corporation, a Delaware corporation ("Range").

                                    Recitals

Whereas, CGI and Range have completed the initial three year term to that
certain Application Service Provider and Outsourcing Agreement ("ASP/OA") dated
June 1, 2000 whereby both parties agree to extend the contract period for an
additional twenty four (24) months.

Whereas, notwithstanding the provisions set out on the ASP/OA, the parties
herein agree to certain changes that will govern the extended contract period,
all other provisions to be governed by the original ASP/OA.

NOW, THEREFORE, in consideration for the mutual promises contained herein, CGI
and Range agree as follows:

                                    Agreement

1.   The term of this extended agreement will commence on the anniversary date
     of the ASP/OA of June 1, 2003 and will end on May 31, 2005. Range will have
     an option to extend the contract for an additional twelve- (12) month
     period at a cost per month equal to the price being paid at the end of the
     twenty four-month anniversary date.

2.   The Base Charge will be set at $90,000 a month for services covered on
     Exhibit B of the ASP/OA. CGI and Range will mutually agree to a change in
     the Base Charge as a result of any material acquisition or divestiture of
     properties based on the level of work added or decreased. The Base Charge
     will include dedicated labor resources to service Range's management, staff
     and technical support and a ten-hour per month management and technical
     consultation. A 3% increase to the Base Charge will be assessed on June 1,
     2004 which is the first day of the thirteenth month of the contract
     extended period.

3.   A $12,000 Prepaid Professional Service Fee will be charged monthly for 120
     hours to be applied to Range designated and approved projects. Any unused
     hours will be carried over from month to month until used or refunded to
     Range at the twenty-four month anniversary of the contract. Professional
     Services hours that exceed the prepaid hours will be charged at CGI's
     current Professional Service rates.

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4.   The Supplemental Agreement dated August 15, 2000 will terminate as of May
     31, 2003.

5.   The independent third party contractor will remain as part of the outsource
     group and be paid by Range Resources until the Joint Interest Billing
     processing can be converted from multiple companies (companies
     2,31,32,41,46) to one operating company. This conversion shall be
     incorporated into the Horizon conversion.

6.   Range Resources will pay Oildex directly for any electronic data exchange
     fees.

7.   Effective with June 1,2003 scanning, imaging and indexing of hard page
     documents will be charged a separate fee of 10 cents per document imaged,
     and an hourly rate charged for document prepping. Hard page documents
     imaged will be logged, labeled and boxed and sent to Range storage
     facility.

8.   The technical services will be divided into two groups - the Development
     and Project group and the Range Outsource technical support group. The
     Development and Project group will be for billable work that can be applied
     to the monthly professional services prepaid hours. CGI agrees to employ
     sufficient technical resources on billable technical projects to assure
     timely targeted timelines on each project. CGI will forfeit 5% of the
     project value if a project is not completed within ninety days of the
     agreed target date. The Range Outsource technical support will be part of
     the monthly Base Charge.

9.   New development software such as the A/P image workflow will not be part of
     the monthly Base Charge. A separate fee will be assessed with Range
     Resources' concurrence.

10.  CGI agrees to have an Independent annual SAS 70 audit to be in compliance
     with Range internal control SEC requirements. The cost of the annual SAS 70
     requirements will be included in the Base Charge.

11.  CGI agrees to move up the Range closing schedule to allow Range to meet the
     new SEC Reporting Guidelines.


12.  Exhibit C of the ASP/OA will be adjusted to reflect the current
     Professional Service hourly rates.

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IN WITNESS WHEREOF, the parties hereto have caused their names to be affixed
hereto as of the date first above written.






                      CGI  INFORMATION SYSTEMS & MANAGEMENT SYSTEMS, INC.



                      By:
                         ------------------------------------------------.


                      Printed Name:
                                   --------------------------------------.


                      Title:
                            ---------------------------------------------.



                      RANGE RESOURCES CORPORATION



                      By:
                         ------------------------------------------------.


                      Printed Name:
                                   --------------------------------------.


                      Title:
                            ---------------------------------------------.