It was narrated that Abu Hurairah said:
"The Messenger of Allah said: 'Whoever loves Hasan and Husain, loves me; and whoever hates them, hates me.'" (RU)
English reference (RU): Vol. 1, Book 1, Hadith 143 (RU)
Arabic reference (RU): Book 1, Hadith 148 (RU)