Quran 2:234 from Surah Al-Baqara on Divine Marvels.
وَٱلَّذِينَ يُتَوَفَّوۡنَ مِنكُمۡ وَيَذَرُونَ أَزۡوَٰجٗا يَتَرَبَّصۡنَ بِأَنفُسِهِنَّ أَرۡبَعَةَ أَشۡهُرٖ وَعَشۡرٗاۖ فَإِذَا بَلَغۡنَ أَجَلَهُنَّ فَلَا جُنَاحَ عَلَيۡكُمۡ فِيمَا فَعَلۡنَ فِيٓ أَنفُسِهِنَّ بِٱلۡمَعۡرُوفِۗ وَٱللَّهُ بِمَا تَعۡمَلُونَ خَبِيرٞ
English translation: And those who pass away among you and leave behind wives (the widows) should wait for themselves (for) four months and ten (days) Then when they reach their (specified) term then (there is) no blame upon you for what they do concerning themselves in a fair manner And Allah of what you do (is) All-Aware
Transliteration: wa-alladhina yutawaffawna minkum wayadharuna azwajan yatarabbasna bi-anfusihinna arba'ata ashhurin wa'ashran fa-idha balaghna ajalahunna fala junaha alaykum fima fa'alna fi anfusihinna bil-ma'rufi wal-lahu bima ta'maluna khabirun