Wang, Chuang, and Hsu (2008) reported the presence
of rutin, quercetin, kaempferol in citrus peel, while Wu, Guan,
and Ye (2007) reported presence of rutin in grape fruit peel,
and Khanam, Oba, Yanase, and Murakami (2012) reported
the presence of rutin in leafy vegetables.