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FindMotif
Try to find Motif (or lesstif)
Once done this will define:
MOTIF_FOUND        - system has MOTIF
MOTIF_INCLUDE_DIR  - include paths to use Motif
MOTIF_LIBRARIES    - Link these to use Motif
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Licensed under the BSD 3-clause License.
 https://cmake.org/cmake/help/v3.6/module/FindMotif.html