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                                                                   Exhibit 4.20

                                   GUARANTEES

                  From and after the date of the Release, each of the
undersigned (the "Guarantors") hereby jointly and severally unconditionally
guarantees, to the extent set forth in the Indenture dated as of December 3,
2002 by and among R.H. Donnelley Finance Corporation I, a Delaware corporation,
as issuer (the "Company"), the Guarantors, as guarantors, and The Bank of New
York, as Trustee (as amended, restated or supplemented from time to time, the
"Indenture"), and subject to the provisions of the Indenture, (a) the due and
punctual payment of the principal of, and premium, if any, and interest on the
Notes, when and as the same shall become due and payable, whether at maturity,
by acceleration or otherwise, the due and punctual payment of interest on
overdue principal of, and premium and, to the extent permitted by law, interest,
and the due and punctual performance of all other obligations of the Company to
the Holders or the Trustee, all in accordance with the terms set forth in
Article Ten of the Indenture, and (b) in case of any extension of time of
payment or renewal of any Notes or any of such other obligations, that the same
will be promptly paid in full when due or performed in accordance with the terms
of the extension or renewal, whether at stated maturity, by acceleration or
otherwise.

                  The obligations of the Guarantors to the Holders and to the
Trustee pursuant to this Guarantee and the Indenture are expressly set forth in
Article Ten of the Indenture, and reference is hereby made to the Indenture for
the precise terms and limitations of this Guarantee. Each Holder of the Note to
which this Guarantee is endorsed, by accepting such Note, agrees to and shall be
bound by such provisions.

                  Each Guarantee will be limited to an amount not to exceed the
maximum amount that can be guaranteed by such Guarantor after giving effect to
all of its other contingent and fixed liabilities without rendering such
Guarantee, as it relates to such Guarantor, voidable under applicable law
relating to fraudulent conveyance or fraudulent transfer or similar laws
affecting the rights of creditors generally.

                         [Signatures on Following Pages]

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                  IN WITNESS WHEREOF, each of the Guarantors has caused this
Guarantee to be signed by a duly authorized officer.

                                  R.H. Donnelley Corporation, as Guarantor

                                  By: /s/ Robert J. Bush
                                      Name:  Robert J. Bush
                                      Title: Vice President

                                  R.H. Donnelley APIL, Inc., as Guarantor

                                  By: /s/ Robert J. Bush
                                      Name:  Robert J. Bush
                                      Title: Vice President

                                  R.H. Donnelley CD, Inc., as Guarantor

                                  By: /s/ Robert J. Bush
                                      Name:  Robert J. Bush
                                      Title: Vice President

                                  Get Digital Smart.com, Inc., as Guarantor

                                  By: /s/ Robert J. Bush
                                      Name:  Robert J. Bush
                                      Title: Vice President

                                  R.H. Donnelley Acquisitions Inc., as Guarantor

                                  By: /s/ Robert J. Bush
                                      Name:  Robert J. Bush
                                      Title: Vice President

                                  R.H. Donnelley Acquisitions II Inc.,
                                        as Guarantor

                                  By: /s/ Robert J. Bush
                                      Name:  Robert J. Bush
                                      Title: Vice President

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                                  DirectoriesAmerica, Inc., as Guarantor

                                  By: /s/ Robert J. Bush
                                      Name:  Robert J. Bush
                                      Title: Vice President

                                  R.H. Donnelley Publishing & Advertising, Inc.,
                                        as Guarantor

                                  By: /s/ Robert J. Bush
                                      Name:  Robert J. Bush
                                      Title: Vice President

                                  R.H. Donnelley Directory Company, as Guarantor

                                  By: /s/ Robert J. Bush
                                      Name:  Robert J. Bush
                                      Title: Vice President

                                  CenDon, L.L.C., as Guarantor

                                  By: /s/ David C. Swanson
                                      Name:  David C. Swanson
                                      Title: Manager

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