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remit any excess collections received by Seller.  Upon the reasonable written
request of Enterra Sub, Seller shall provide it with a status report concerning
the collection of assigned receivables.

     Section 12.3 Expenses. The Purchasers and the Seller will each pay their
own expenses in connection with the transactions contemplated hereby.

     Section 12.4 Brokers and Finders. Neither the Purchasers nor the Seller
shall be responsible to the other party for the payment of any broker's fee,
finder's fee or commission of any sort in connection with the transactions
described herein. The Seller shall be responsible for payment of any such fee to
Wertheim Schroder & Co. Incorporated or any other party to which the Seller has
such an obligation. The Purchasers shall be responsible for payment of any such
fee to Simmons & Company International, Inc. or any other party to which the
Purchasers have such an obligation.

     Section 12.5 Entire Agreement; Assignment. This Agreement constitutes the
entire agreement among the parties and their Affiliates with respect to the
subject matter hereof and supersedes all other prior agreements and
understandings, both written and oral, among the parties and their Affiliates or
any of them with respect to the subject matter hereof. This Agreement and all of
the provisions hereof shall be binding upon and inure to the benefit of the
parties hereto and their respective permitted successors and assigns, but
neither this Agreement nor any of the rights, interests and obligations
hereunder shall be assigned by any of the parties hereto without the prior
written consent of the other parties, except that this Agreement may be assigned
to an Affiliate by any party without the prior written consent of another party;
provided however, that notwithstanding such assignment, the assignor shall
remain liable for all obligations hereunder.

     Section 12.6 Further Assurances. From time to time as and when requested by
the Purchasers, the Seller shall execute such further agreements, assignments,
documents, deeds, certificates and other instruments of conveyance and transfer
and to take or cause to be taken such other actions as the Purchasers may
reasonably require to vest title to the Assets in the Purchasers and as shall be
reasonably necessary or advisable to carry out the purposes of and to effect the
transactions contemplated by this Agreement.

     Section 12.7 Enforcement of the Agreement. The parties hereto agree that
irreparable damage would occur in the event that any of the provisions of this
Agreement were not performed in accordance with their specific terms or were
otherwise breached. It is accordingly agreed that the parties shall be entitled
to an injunction or injunctions to prevent breaches of this Agreement and to
enforce specifically the terms and provisions hereof, this being in addition to
any other remedy to which they are entitled pursuant to the terms hereof or
otherwise, at law or in equity.

     Section 12.8 Severability. If any provision of this Agreement is held to be
illegal, invalid or unenforceable under present or future laws in any
jurisdiction, that provision shall be ineffective to the extent of such
illegality, invalidity or unenforceability in that jurisdiction and such holding
shall not, consistent with applicable law, invalidate or render unenforceable
such provision in any other jurisdiction, and the legality, validity and
enforceability of the remaining provisions of this Agreement shall not be
affected thereby, and shall remain in full force and effect in all
jurisdictions.

     Section 12.9 Notices. All notices, requests, claims, demands and other
communications hereunder shall be in writing and shall be deemed to have been
duly given when delivered by registered mail (postage prepaid, return receipt
requested) or prepaid Federal Express (return receipt requested) to the
respective parties as follows:
 

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