Mukhtasar Bukhari (Abridged) 2057 — Few should greet the many

Narrated from Sayyiduna Abu Hurairah (may Allah be pleased with him) that the Noble Prophet (peace and blessings of Allah be upon him) said: "The younger should greet the older, the one who is walking should greet the one who is sitting, and a smaller group should greet a larger group."