Supoj Muenvanitchakul. 1989. Effects of different planting dates on growth, yield and oil content of sunflowers (Helianthus annuss L.). Graduate School, Khon Kaen University;
Supoj Muenvanitchakul. (1989) Effects of different planting dates on growth, yield and oil content of sunflowers (Helianthus annuss L.) . Khon Kaen University/Khon Kaen.
Supoj Muenvanitchakul. Effects of different planting dates on growth, yield and oil content of sunflowers (Helianthus annuss L.). . Khon Kaen:Khon Kaen University, 1989.
Supoj Muenvanitchakul. (1989) Effects of different planting dates on growth, yield and oil content of sunflowers (Helianthus annuss L.) . Khon Kaen University/Khon Kaen.