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                                                                    EXHIBIT 3.47

[SEAL]

                          CERTIFICATE OF INCORPORATION

                                       OF

                             KAGAN WORLD MEDIA, INC.

     THE UNDERSIGNED, in order to form a corporation for the purposes herein
stated, under and pursuant to the provisions of the General Corporation Law of
the State of Delaware, does hereby certify as follows:

     FIRST:    The name of the Corporation is KAGAN WORLD MEDIA, INC.
     (hereinafter, the "Corporation").

     SECOND:   The registered office of the Corporation is to be located at The
Prentice-Hall Corporation System, Inc., 229 South State Street, Dover, County of
Kent, Delaware 19901. The name of its registered agent at that address is The
Prentice-Hall Corporation System, Inc.

     THIRD:    The purpose of the Corporation is to engage in any lawful act or
activity, without limitation, for which a corporation may be organized under the
General Corporation Law of the State of Delaware.

     FOURTH:   The total number of shares of all classes of stock which the
Corporation is authorized to issue is Three Thousand (3000) shares, consisting
entirely of Common Stock, of no par value ($0.00) per share.

     FIFTH:    The name and mailing address of the sole incorporator is:

<Table>
<Caption>
        Name                    Address
        ----                    -------
                       
     Paula A. Day         721 Lighthouse Avenue
                          P.O. Box 607
                          Pacific Grove, CA 93950
</Table>

     SIXTH:    The election of directors need not be by written ballot unless
the By-laws so provide.

     SEVENTH:  The Board of Directors of the Corporation is authorized and
empowered from time to time in its discretion to

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make, alter, amend or repeal the By-laws of the Corporation, except as such
power may be restricted or limited by the General Corporation Law of the State
of Delaware.

     EIGHTH:   Whenever a compromise or arrangement is proposed between this
Corporation and its creditors or any class of them and/or between this
Corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this Corporation or of any creditor or stockholder thereof or on the
application in a summary way of this Corporation or of any creditor or
stockholder thereof or on the application of any receiver or receivers appointed
for this Corporation under the provisions of Section 291 of Title 8 of the
Delaware Code or on the application of trustees in dissolution or of any
receiver or receivers appointed for this Corporation under the provisions of
Section 279 of Title 8 of the Delaware Code order a meeting of the creditors or
class of creditors, and/or of the stockholders or class of stockholders of this
Corporation, as the case may be, to be summoned in such manner as the said court
directs. If a majority in number representing three-fourths in value of the
creditors or class value of the creditors or class of creditors and/or of the
stockholders of this Corporation, as the case may be, agree to any compromise or
arrangement and to any reorganization of this Corporation as a consequence of
such compromise or arrangement, the said compromise or arrangement and the said
reorganization shall, if sanctioned by the court to which the said application
has been made, be binding on all creditors or class of creditors, and/or all the
stockholders or class of stockholders of this Corporation, as the case may be,
and also on this Corporation.

     NINTH:    The Corporation reserves the right to amend, alter, change or
repeal any provision contained in this Certificate of Incorporation in the
manner now or hereafter prescribed by law, and all rights and powers conferred
herein on stockholders, directors and officers are subject to this reserved
power.

     TENTH:    The personal liability of the directors of the Corporation is
hereby eliminated to the fullest extent permitted by paragraph (7) of subsection
(b) of Section 102 of the General Corporation Law of the State of Delaware, as
the same may be amended and supplemented.

     ELEVENTH: The Corporation shall, to the fullest extent permitted by Section
145 of the General Corporation Law of the State of Delaware, as the same may be
amended and supplemented,

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indemnify any and all persons who it shall have power to indemnify under said
section from and against any and all of the expenses, liabilities or other
matters referred to in or covered by said section, and the indemnification
provided for herein shall not be deemed exclusive of any other rights to which
those indemnified may be entitled under any By-laws, agreement, vote of
stockholders or disinterested directors or otherwise, both as to action in his
official capacity and as to action in any other capacity while holding such
office, and shall continue as to a person who has ceased to be a director,
officer, employee or agent and shall inure to the benefit of the heirs,
executors and administrators of such a person.

     IN WITNESS WHEREOF, I have hereunto set my hand this 11th day of July 1989.


                                                      /s/ Paula A. Day
                                                      --------------------------
                                                      Paula A. Day,
                                                      Sole Incorporator
                                                      721 Lighthouse Ave.
                                                      P.O. Box 607
                                                      Pacific Grove, CA 93950

ArtInc.kwm

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