T. HUSAIN, A. GARG, P. AGNIHOTRI, and R. R. MILL, “A REVISION OF PEDICULARIS SERIES CURVIPES (PRAIN) HURUS. (OROBANCHACEAE)”, Edinburgh J. Bot., vol. 63, no. 1, pp. 49–65, Aug. 2006, doi: 10.1017/S0960428606000412.