الوصول الحر: https://escholarship.org/uc/item/0b19r9ppTest
الإتاحة: https://doi.org/10.1016/j.regpep.2010.07.164Testhttps://api.elsevier.com/content/article/PII:S0167011510003198?httpAccept=text/xmlTesthttps://api.elsevier.com/content/article/PII:S0167011510003198?httpAccept=text/plainTest