Warittha Thongsamut และผู้แต่งคนอื่นๆ. (2010) Effects of Plant Spacing on Light Interception, Growth and Yield of Sunflower (Helianthus annuus L.). <i>Thai Agricultural Research Journal</i>, <i>28</i>(2), 187-203.Warittha Thongsamut และผู้แต่งคนอื่นๆ. "Effects of Plant Spacing on Light Interception, Growth and Yield of Sunflower (Helianthus annuus L.)". Thai Agricultural Research Journal 28 (2010):187-203.Warittha Thongsamut และผู้แต่งคนอื่นๆ. Effects of Plant Spacing on Light Interception, Growth and Yield of Sunflower (Helianthus annuus L.). Department of Agriculture:ม.ป.ท. 2010.