"As Salaamu Alaikum Wa Rahmatullahi Wa Barakatuhu,
It has been noticed that a latecomer (Masbooq) for Salah finds the Imam in Ruku(bowing position), whilst saying Takbeer Tahreema (Opening Takbeer) he dives into Ruku, his Takbeer Tahreema(First Allahu-Akbar) finishes in Ruku.
What is the ruling regarding his salah?"
(درر الحكام شرح غرر الأحكام ، كتاب الصلاة ، صفة الصلاة الصفحة ٦٥ الجزء ١)
 Fatawa Hindiyyah is a collection of Islamic rulings issued and compiled by a group of Hanafi scholars from India. This scholarly work was in response to a request by the Muslim king of India and an Islamic scholar in his own standing, Muhammad Aurangzeb. The Mughal Emperor Aurangzeb (who was also known as 'Alamgir').
 Radd al-Muhtar `ala Durr al-Mukhtar: "The Answer to the Baffled" over "The Exquisite Pearl" is the explanation of Durr al-Mukhtar by `Allamah Sayyid Muhammad Ameen ibn `Aabideen ash-Shaami rahimahullah
Radd al-Muhtar (also famous as Hashiyat Ibn Abidin and, in the Subcontinent, as Shami) is the central reference for fatwa and legal details in the Hanafi school across the Muslim world because of the methodology used by its author. He first studied the principles of weighing legal opinions (rasm al-mufti or qawa`id al-ifta'), and then systematized these, resolving apparent differences in methodology between the great imams of verification of the Hanafi school. After this, he applied this methodology is a very balanced and consistent manner throughout his work