It doesn t happen often, but you might come across a newspaper article with no author or an unknown author in your citations.

http://skillnet.instructure.com/eportfolios/9294/Modiodal_100_Mg_L_Equals__TEVA__StayAwake
http://sunet.instructure.com/eportfolios/1510/Modavigil_100_Mg_Nicotine__Signature_Pharmaceuticals__StayAwake

縺ゅ縺 メッセージ
3 percent positivity rate average over the last week, according to its dashboard site.