Crepe - black silk or imitation silk, formerly used for mourning clothes. New Oxford American Dictionary, 3rd Edition © 2010 by Oxford University Press Inc.

prints, particularly woodcuts have been (sometimes still are) made on the so-called crêpe paper. However, Van Gogh habitually used this term for Japanese prints in general. To be safe, you may wish to skip "Japanese" and just say “как на гравюрах/эстампах“.

Please have a look: http://vangoghletters.org/vg/terminology.html

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Note added at 2 hrs (2012-01-02 11:03:34 GMT)
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При жизни, он охотно поменял бы гравюру-другую на тарелку блинчиков. :)