{Say: He is Allah, the One.} The Messenger of Allah, peace and blessings be upon him, said: "It has become obligatory." I said: "What has become obligatory?" He said: "Paradise." (1)

This is a good, authentic, and unfamiliar hadith. We do not know it except from the narration of Malik ibn Anas. And Ibn Hunayn (2): he is 'Ubayd ibn Hunayn.

3120 - Muhammad ibn Marzuq al-Basri narrated to us, saying: Hatim ibn Maymun Abu Sahl narrated to us, from Thabit al-Bunani, from Anas ibn Malik, from the Prophet, peace and blessings be upon him, who said: "Whoever recites {Say: He is Allah, the One} two hundred times every day, the sins of fifty years will be wiped away from him, unless he has a debt upon him." (3)

3121 - And by this same chain of transmission, from the Prophet, peace and blessings be upon him, who said: "Whoever wishes to sleep on his bed and sleeps on his right side, then recites {Say: He is Allah, the One} one hundred times, then on the Day of Resurrection the Lord will say to him: 'O My servant, enter Paradise on your right side.'" (4)

This is an unfamiliar hadith among the narrations of Thabit from Anas.

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(1) Authentic hadith, also recorded by al-Nasa'i 2/171. It is in the "Musnad" of Ahmad (8011).
(2) The correction is from (L), and it is correct; in the other manuscript sources it reads: "And Abu Hunayn."
(3) Its chain is weak due to the weakness of Hatim ibn Maymun. Also recorded by Abu Ya'la (3365), and Ibn 'Adi in "al-Kamil" 2/845.
(4) Its chain is weak like the previous one, and it was recorded by Ibn 'Adi in "al-Kamil" 2/845.