P. P. SREEJITH, C. PRASAD, K. R. NATH, S. SURESH, N. LEEMON, and S. NAJEEB, “QUALITATIVE PATTERNS OF MORPHOLOGICAL CHARACTERIZATION IN THE FEATHERS OF FLYING AND FLIGHTLESS BIRDS”, UPJOZ, vol. 41, no. 18, pp. 1–12, Nov. 2020.