In the Ramayana the four sons of Dasharatha marry as follows
Rama – Sita, Lakshmana – Urmila, daughters of king Janaka.
Bharata – Mandavi, Shatrugna – Shrutakirti, daughters of king Janakas brother, king Kushadhvaja.
Lakshmana and Urmila – including marriage of Shatrugna and Bharata
Lakshmana and Urmila