Sayyiduna Zayd bin Khalid al-Juhani (may Allah be pleased with him) asked Uthman bin Affan (may Allah be pleased with him) about a man who has intercourse but does not ejaculate. He said: "There is no ghusl upon him." Then he said: "I heard this from the Messenger of Allah (peace and blessings be upon him)." Then he said: After that I asked Ali bin Abi Talib, al-Zubayr bin al-Awwam, Talhah bin Ubaydullah and Ubayy bin Ka'b (may Allah be pleased with them), and they related the same from the Prophet (peace and blessings be upon him).
(b) In the hadith of Abu Qilabah: "Only ablution is required for it."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 771