Iorio RM, Field GM, Sauvron JM, Mirza AM, Deng R, Mahon PJ, Langedijk JP. Structural and functional relationship between the receptor recognition and neuraminidase activities of the Newcastle disease virus hemagglutinin-neuraminidase protein: receptor recognition is dependent on neuraminidase activity. J Virol. 2001 Feb; 75(4):1918-27.