... may prepare ... or commission the preparation thereof.
... may prepare ... or arrange for the preparation thereof.

These are possible ways of expressing this in formal, legal language.

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Note added at 52 mins (2011-09-22 10:53:01 GMT)
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The following pattern is even better, because it removes the need for 'thereof'.

http://www.legislation.govt.nz/act/public/1987/0065/latest/D...

prepare, or commission the preparation of, plans for the conservation, management, and control, or any of them, of any natural and historic resource:

Yes, follow the same pattern.

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Note added at 4 hrs (2011-09-22 14:58:41 GMT)
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Another valid possibility:

http://www.austlii.edu.au/au/legis/qld/consol_act/cfa1958149...

Where, in any case referred to in section 5, the trustees or a majority of the trustees of the fund or of any property in the fund are desirous that the same shall be dealt with under and subject to this Act, they may prepare or cause to be prepared, and submit or cause to be submitted to a certifying officer, a scheme for dealing with the fund or any part or residue thereof under and in accordance with this Act.