My friend likes to marry an srilankan girl. He is a Indian. How to register this marriage legally?

She lives in UK (srilankan citizen). They are planing to have their marriage in India this december. What are the formalities that has to be done to make this marriage a legal one. Please advice. ThanksMy friend likes to marry an srilankan girl. He is a Indian. How to register this marriage legally?
THey have to get the paper work and get a lawyer for citizenship puposes and stuff.My friend likes to marry an srilankan girl. He is a Indian. How to register this marriage legally?
careful man.......

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