7Alexander J Simone. Pet chew product having oral care properties : US,005,296,209A[P]. 1994-03-22.
8Anthony Lawlor. Easily-digestible pet chew that promotes oral health and prevents malodorous breath in animals, and method of making thereof:US,007,662,414B1[P]. 2010-02-16.
9Valentina Stojceska,Paul Ainsworth,Andrew Plunkett,et al. The effect of extrusion cooking using different water feed rates on the quality of ready-to-eat snacks made from food byproducts[J]. Food Chemistry, 2009,114 : 226-232.
10Frederic Robin,Jan Engmann,Nicolas Pineau,et al. Extrusion, structure and mechanical properties of complex starchy foams[J]. Journal of Food Engineering, 2010,98 : 19-27.
