Tham khảo Zelkova

    • Andrews, S. (1994). Tree of the year: Zelkova. Int. Dendrol. Soc. Yearbook 1993: 11-30.
    • de Spoelberch, P. (1994). Zelkova: More questions than answers. Int. Dendrol. Soc. Yearbook 1993: 30-33.
    • Hunt, D. (1994). Beware of the Zelkova. Int. Dendrol. Soc. Yearbook 1993: 33-41.
    • Rushforth, K. (1999). Trees of Britain and Europe. HarperCollins ISBN 0-00-220013-9