1. Interrelationship of morphological and economic characters of sunflower;Beard B. H.;Crop Sciences,1982
2. Reaction of sunflower hybrids in comparison with varieties to agronomic measures of cultivation;Belevtsev D. N.;Vestnik Selskokhozyaistvennoi Nauki, Moszkva,1991
3. Sowing date and seed covering depth;Belevtsev D. N.;Tekhnicheskie Kultury,1990
4. Research on sunflower sowing date in the area of red brown soils on the Romanian Plateau;Bilteanu G.;Productia Vegetala Cereale si Plante Tehnice,1986
5. The dinamics of sunflower emergence, flowering and ripening in relation to sowing date and seed treatment;Encseva V.;Rastenievdni Nauki,1984