Microstructured barbs on the North American porcupine quill enable easy tissue penetration and difficult removal
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TWAG 1990-09-06, Faculty Issue - This Week at Gettysburg, September 06-16, 1990 - Gettysburg College Publications - GettDigital: Gettysburg College Digital Collections
![THE BARB'XPERT BY FRANCK PROVOST - KIT ENTRETIEN BARBE - Accessoires et cosmétique pour une barbe bien entretenue. - Cdiscount Au quotidien THE BARB'XPERT BY FRANCK PROVOST - KIT ENTRETIEN BARBE - Accessoires et cosmétique pour une barbe bien entretenue. - Cdiscount Au quotidien](https://www.cdiscount.com/pdt2/1/9/1/1/700x700/fra3700206706191/rw/the-barb-xpert-by-franck-provost-kit-entretien-b.jpg)