@patent{rathi@15,
	author={Rathinavelu Chengalvarayan, et al},
	institution={{US8050928B2}},
	month={November},
	title={Speech to DTMF generation},
	url={http://www.research.att.com/export/sites/att_labs/people/Chengalvarayan_Rathinavelu/library/patents/US8050928B2.pdf},
	year=2011,
}