Bollywood producer Mukesh Bhatt says Sidharth Malhotra and Alia Bhatt have been signed for the third installment of “Aashiqui”, as the duo are perfect for the roles.“Yes, it is true. We have signed Sidharth and Alia for the film. They completely fit the role. When we make films we look for the perfect casting. They both fit the bill,” Bhatt told.