Reference : Hisn al-Muslim 152

لا إلهَ إلاّ اللّهُ
وَاللّهُ أَكْبَـر،
لا إلهَ إلاّ اللّهُ وحْـدَهُ،
لا إلهَ إلاّ اللّهُ
وحْـدَهُ لا شَريكَ لهُ،
لا إلهَ إلاّ اللّهُ
لهُ المُلكُ ولهُ الحَمْد،
لا إلهَ إلاّ اللّهُ
وَلا حَـوْلَ وَلا قُـوَّةَ إِلاّ بِالله
Lā ilāha illallāh
wallāhu Akbar, 
lā ilāha illallāhu waḥdah,
lā ilāha illallāh
waḥdahu lā sharīka lah, 
lā ilāha illallāh
lahu ‘l-mulku wa lahu ‘l-ḥamd, 
lā ilāha illallāh
wa lā ḥawla wa lā quwwata illā billāh.


There is none worthy of worship but Allah, 
Allah is the Most Great. 
None has the right to be worshipped but Allah alone. 
None has the right to be worshipped but Allah alone, 
Who has no partner. 
There is none worthy of worship but Allah,
His is the dominion and His is the praise.
There is none worthy of worship but Allah,
there is no power and no might but by Allah.

Reference:
At-Tirmidhi and Ibn Majah. See also Al-Albani, Sahih At-Tirmidhi 3/152 and 
Sahih Ibn Majah 2/317.

Chapter: When the sick have renounced all hope of life