Abu Ja'far (may Allah have mercy on him) said: I saw Sayyiduna Ibn Abbas (may Allah be pleased with him) come on the Day of Tarwiyah. He kissed the Corner, then prostrated on it, then kissed it, then prostrated on it, three times.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 9224