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                                                                 EXHIBIT 4.20(b)



                               FOURTH AMENDMENT TO
                         RECEIVABLES PURCHASE AGREEMENT


         THIS FOURTH AMENDMENT TO RECEIVABLES PURCHASE AGREEMENT, dated as of
August 16, 2000 (this "Amendment"), is entered into between GAYLORD CONTAINER
CORPORATION, a Delaware corporation ("Gaylord"), as Seller and GAYLORD
RECEIVABLES CORPORATION, a Delaware corporation ("GRC"), as Purchaser.

                                    RECITALS:

         WHEREAS, GRC and Gaylord are parties to the Receivables Purchase
Agreement dated as of September 24, 1993, as amended prior to the date hereof
(as so amended, the "Agreement"); and

         WHEREAS, the parties hereto desire to amend the Agreement as
hereinafter set forth.

         NOW THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties agree as follows:

         1. Defined Terms. Capitalized terms used but not defined herein have
the meaning set forth in Appendix A to the Agreement.

         2. Section 8.2(d) of the Agreement is hereby amended and restated in
its entirety as follows:

                  (d) The agreement of the Seller to sell Receivables hereunder,
         and the agreement of GRC to purchase Receivables from the Seller
         hereunder, shall terminate automatically on the occurrence of the
         Liquidation Commencement Date unless the Seller elects to continue to
         sell Receivables to GRC pursuant to Section 1.2(c); provided that,
         notwithstanding the foregoing, if, at any time prior to the Liquidation
         Commencement Date, a Liquidation Event occurs pursuant to Section
         9.01(d) of the Pooling and Servicing Agreement as a result of an
         involuntary bankruptcy proceeding being filed against the Seller, then,
         notwithstanding anything to the contrary in such Section 9.01(d) or in
         the definition of "Liquidation Commencement Date," on and after the day
         on which such an involuntary bankruptcy proceeding is filed, GRC shall
         cease to purchase Receivables and Related Assets from the Seller and to
         transfer Receivables and Related Transferred Assets to the Trust; and
         provided further that GRC may resume such purchases and transfers if,
         within ten days after any such filing, (i) GRC or the Seller shall have
         obtained an order from the court conducting such involuntary bankruptcy
         proceeding (A) authorizing the Seller to continue to make sales of
         Receivables and Related Assets to GRC and (B) confirming that such
         sales, and any security interest related thereto, will not be voidable
         as a postpetition transaction under Section 549



                                                             Fourth Amendment to
                                                  Receivables Purchase Agreement


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         of the Bankruptcy Code (or any other equivalent provision of law) and
         (ii) counsel to the Seller and to GRC shall have reaffirmed the
         conclusions in the opinions delivered pursuant to Section 4.1(j)(i)
         which reaffirmation shall be reasonably acceptable to the Seller, GRC,
         the Trustee and S&P.

         3. The definitions of "Class A-RI Certificate" and "Discount Rate
Reserve" set forth in Appendix A to the Agreement are hereby amended and
restated in their entirety as follows:

                  "Class A-RI Certificate" means each Revolving Certificate
         which is designated as such and which represents a right to receive a
         variable principal amount, bears interest at a Class A-RI Certificate
         Rate, is executed by GRC and authenticated by or on behalf of the
         Trustee, and is substantially in the form of an exhibit to the
         Supplemental Issuance Agreement pursuant to which such series of
         Revolving Certificates is issued.

                  "Discount Rate Reserve" means, at any time, an amount equal to
         the sum of (in each case, without duplication):

                  (a) (i) the accrued and unpaid Carrying Costs as set forth in
         the then-effective Settlement Statement, plus (ii) the amount of
         Carrying Costs (other than Servicing Fees) that will, or are estimated
         to, have accrued by the next Settlement Date, as set forth in the then-
         effective Settlement Statement, plus

                  (b) the Servicing Fee Reserve, as set forth in the then
         effective Settlement Statement, plus

                  (c) an amount equal to (i) the Investor Invested Amount, times
         (ii) the weighted average of the interest rates per annum applicable to
         each series of Investor Certificates, in the case of each of the
         foregoing, as of the most recent Cut-Off Date times (iii) 25.0%, minus

                  (d) the portion of the aggregate balance in the Master
         Collection Account that is allocated to the Carrying Cost Account as of
         such time.

         4. The definition of "Excess Concentration Balance" set forth in
Appendix A to the Agreement is hereby amended by replacing clause (d) thereof
with the following:

                  (d) 3% for any one (1) other Obligor and 2% for each other
         Obligor that, in each case, is not an Obligor provided in clauses (a),
         (b) or (c) above.

         5. Each of the following definitions is hereby added, alphabetically,
to Appendix A to the Agreement:

                  "Average Days Sales Outstanding" means any period (expressed
         in a number of days) calculated as: (i) the average of the aggregate
         Unpaid Balance of all Receivables as of the

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                                                  Receivables Purchase Agreement


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         applicable Cut-Off Date for each of the three immediately preceding
         Calculation Periods, multiplied by (ii) 91, divided by (iii) the
         aggregate amount of invoices giving rise to Receivables generated
         during the immediately preceding three Calculation Periods.

                  "Average Dilution Ratio" means, for any three consecutive
         Calculation Periods, a ratio equal to the sum of the Dilution Ratios
         shown on the Settlement Statement for each such Calculation Period
         divided by 3.

                  "Authenticating Agent" means the Trustee or any other
         authenticating agent appointed by the Trustee pursuant to Section
         6.11(a) of the Pooling and Servicing Agreement.

                  "Series Fee Amount" means, (i) for Series 2000-1 A-RI
         Certificates, the aggregate amount of fees set forth in the Collateral
         Agent Fee Letter and the Facility Agent Fee Letter (as each such term
         is defined in the Amended and Restated Credit Agreement entered into in
         connection with Series 2000-1 Certificates), and (ii) for any other
         series of Certificates, the amount of regularly scheduled monthly or
         annual fees payable to the Trustee, or any agent for direct or indirect
         investors in, or lenders secured by, such Certificates pursuant to this
         Agreement, the applicable Supplemental Issuance Agreement or any
         related agreement; it being understood that extraordinary fees,
         expenses or indemnity obligations are not included in the Series Fee
         Amount but may be included in Accrued Carrying Costs.

                  "Series Majority Investors" means, with respect to any series
         of Investor Certificates, the Holders of such series of Investor
         Certificates that evidence an aggregate principal amount of more than
         50% of the aggregate outstanding principal amount of such series of the
         Investor Certificates.

                  "Servicing Fee Base Amount", with respect to any Settlement
         Date, the portion of the Carrying Cost Reserve that would be
         attributable to the Servicing Fees if the Servicing Fees for any
         Calculation Period were equal to one-twelfth of the product of (a) 2.0%
         and (b) the aggregate Unpaid Balance of the Receivables measured on the
         first Business Day of the most recently ended Calculation Period.

                  "Servicing Fee Excess" means, for any Calculation Period, the
         excess (if any) of (x) Servicing Fee for such period over (y) the
         Servicing Fee Base Amount for such period.

                  "Servicing Fee Reserve" means, Servicing Fees that will, or
         are estimated to, have accrued by the Specified Date.

                  "Specified Date" means, with respect to any date of
         determination, the date following the date of such determination that
         is 2 times the Average Days Sales Outstanding as shown in the then most
         recent Settlement Statement.


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                                                  Receivables Purchase Agreement


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         6. Representations and Warranties. Each of GRC and Gaylord hereby
represents and warrants as follows: The execution and delivery by it of this
Amendment, and the performance of its obligations under this Amendment and the
Agreement, as amended hereby, are within its corporate powers and have been duly
authorized by all necessary corporate action on its part. The Agreement (as
amended hereby) is its valid and legally binding obligations, enforceable in
accordance with its terms, except as enforceability may be limited by
bankruptcy, insolvency, reorganization or other similar laws affecting the
enforcement of creditors' rights generally and by general principles of equity,
regardless of whether such enforceability is considered in a proceeding in
equity or at law.

         7. Effect of Amendment. All provisions of the Agreement, as expressly
amended and modified by this Amendment, shall remain in full force and effect.
After this Amendment becomes effective, all references in the Agreement (or in
any other Transaction Document) to this Agreement shall be deemed to be
references to this Agreement as amended hereby.

         8. Counterparts. This Amendment may be executed in any number of
counterparts and by different parties on separate counterparts, each of which
when so executed shall be deemed to be an original and all of which when taken
together shall constitute but one and the same instrument.

         9. Governing Law. This Amendment shall be governed by, and construed in
accordance with, the internal laws of the State of New York.

         10. Section Headings. The various headings of this Amendment are
included for convenience only and shall not affect the meaning or interpretation
of this Amendment, the Agreement or any provision hereof or thereof.


                            [SIGNATURE PAGES FOLLOW]


                                                             Fourth Amendment to
                                                  Receivables Purchase Agreement

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         IN WITNESS WHEREOF, the parties have executed this Amendment as of the
date first written above.


                                            GAYLORD CONTAINER CORPORATION,
                                            as the Seller



                                            By:
                                               ---------------------------------
                                               Name:
                                               Title:


                                            GAYLORD RECEIVABLES CORPORATION,
                                              as the Purchaser


                                            By:
                                               ---------------------------------
                                               Name:
                                               Title:



                                 4th Amendment to Receivables Purchase Agreement


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