1. Barritt, B. H., Konishi, B. and Dilley, M. 2008. Performance of Four High Density Apple Orchard Systems with ‘Fuji’ and ‘Braeburn’. Acta Hort., 772: 389-394.
2. Buler, Z. and Mika, A. 2007. Growth, Yield and Fruit Quality in ‘Sampion’ Apple Trees Trained Using Four Different Training Systems: Hytec, Solen, Mikado and spindle. J. Fruit Ornam. Plant Res., 15: 117-124.
3. Choi, J. J., Gu, M., Choi, J. H., Han, J. H., Yim, S. H., Kim, Y. K., Jung, S. K. and Choi, H. S. 2014. Growth and Fruit Production of Asian Pear Trees Grown on Y-, T-, and Vase-Training Systems. Hort. Environ. Biotechnol., 55(1): 1-8.
4. Costes, E., Sinoquet, H., Kelner, J. J. and Godin, C. 2003. Exploring Within-Tree Architectural Development of Two Apple Tree Cultivars over 6 Years. Annal. Bot., 91: 91-104.
5. Dadashpour, A., Sadegh-Hasani, S. and Mirahmadi, S. F. 2011. Investigation of Some Vegetative and Reproductive Characteristics of Five Apple Cultivars in ‘Guttingen V’ System. J. Ornam. Hort. Plant., 1(2): 55-61.
6. Dadashpour, A., Shakouri, M. J., Shojaie, Z. F. and Dodangeh, M. R. 2012. Evaluation of Growth, Yield and Fruit Characteristics of Five Apple Cultivars on ‘Guttingen V’ System during 2006-2008. Indian J. Sci. Technol., 5(1): 1840-1843 .
7. Dorigoni, A., Lezzer, P., Dallabetta, N., Serra, S. and Musacchi S. 2011. Bi-axis: An Alternative to Slender Spindle for Apple Orchards. Acta Hort., 903: 581-588.
8. Gandev, S. and Dzhuvinov, V. 2014. Training and Pruning of Apple and Modern Trends of Development: An Overview. Turk. J. Agri. Nat. Sci., 1(Special Issue): 1264-1267.
9. Hampson, C. R., Quamme, H. A. and Brownlee R. T. 2002. Canopy Growth, Yield and Fruit Quality of ‘Royal Gala’ Apple Trees Grown for Eight Years in Five Tree Training Systems. HortSci., 37(4): 627-631.
10. Hampson, C. R., Quamme, H. A., Kappel, F. and Brownlee R. T. 2004. Varying Density with Constant Rectangularity: II. Effects on Apple Tree Yield, Fruit Size, and Fruit Colour Development in Three Training Systems over Ten Years. HortSci., 39(3): 507-511.
11. Hassan, H. S. A., Sarrwy, S. M. A., Mostafa, E. A. M. and Dorria, M. A. 2010. Influence of Training Systems on Leaf Mineral Contents, Growth, Yield and Fruit Quality of ‘Anna’ Apple Trees. Res. J. Agric. Biol. Sci., 6(4): 443-448.
12. Inomata, Y., Kudo, K., Wada, M., Masuda, T., Bessho, H. and Suzuki, K. 2004. The Influence of the Training System on Characteristics of Tree Growth, Fruit Productivity and Dry Matter Production of Columnar-type Apple Tree ‘Maypole’. Hort. Res. (Japan), 3(4): 387-392.
13. Jung, S. K. and Choi, H. S. 2010. Light Penetration, Growth and Fruit Productivity in ‘Fuji’ Apple Trees Trained to Four Growing Systems. Sci. Hort., 125(4): 672-678.
14. Kwon, Y. H., Park, Y. S. and Park, J. E. 2011. Changes of Fruit Characteristics by Fruit Load Control in ‘Niitaka’ and ‘Whangkeumbae’ Pear Trees on Y-trellis Training System. Korean J. Hort. Sci. Technol., 29(6): 523-530.
15. Lauri, P. E. 2009. Developing a New Paradigm for Apple Training. The Compact Fruit Tree, 42(2): 17-19.
16. Licznar-Małańczuk, M. 2006. Training System and Fruit Quality in the Apple Cultivar ‘Jonagold’. J. Fruit Ornam. Plant Res., 14(2): 213-218.
17. Monney, P. and Evéquoz, N. 1999. A Study of New Orchard Systems for Apple Trees. Rev. Suisse Viti. d’Arbori. d’Horti., 31(3): 153-158.
18. Ozkan, Y., Yildiz, K., Küçüker, E., Çekiç, Ç., Özgen M. and Akça Y. 2012. Early Performance of cv. Jonagold Apple on M.9 in Five Tree Training Systems. Hort. Sci. (Prague), 39(4): 158-163.
19. Platon, I.V. 2007. Preliminary Results on Planting System and Density in Apple. Acta Hort., 732: 471-473.
20. Porębski, S., Rzeźnicka, B. and Banach, P. 2008. Influence of the Type of Tree Crown on the Growth and Fruiting of ‘Florina’ Apple Trees. Zesz. Nauk. ISiK Skierniewice, 16: 13-19.
21. Robinson, T. L. 2000. V-shaped Apple Planting Systems. Acta Hort., 513: 337-347.
22. Robinson, T. L. 2007. Effects of Tree Density and Tree Shape on Apple Orchard Performance. Acta Hort., 732: 405-414.
23. Rutkowski, K., Kantorowicz-Bąk, M. and Pacholak, E. 2009. Effect of Different Tree Training Systems on Growth and Yielding of Two Apple Cultivars. J. Fruit Ornam. Plant Res., 17(1): 49-59.
24. Shafiq, M., Singh, Z. and Khan, A. S. 2014. Pre-harvest Ethephon Application and Training Systems Affect Colour Development, Accumulation of Flavonoids and Fruit Quality of ‘Cripps Pink’ Apple. Australian J. Crop Sci., 8(12): 1579-1589.
25. Sosna, I. 2004. Evaluation of Some Training Systems in Apple Orchard. J. Fruit Ornam. Plant Res., 12(Special Edition): 85-90.
26. Talaie, A., Shojaie-Saadee, M., Dadashpour A. and Asgari-Sarcheshmeh M. A. 2011. Fruit Quality in Five Apple Cultivars Trees Trained to Intensive Training System: Geneva Y-trellis. Genetika, 43(1): 153-161.
27. Uselis, N. 2003. Growth and Productivity of Dwarf Apple Trees in Bearing Orchards of Various Constructions. Sodininkyste ir Daržininkyste, 22(1): 3-13.
28. Uselis, N., Lanauskas, J. and Kviklys, D. 2007. Productivity and Fruit Quality of Apple Tree cv. ‘Alva’ under Different Orchard Constructions. Sodininkyste ir Daržininkyste, 26(4): 30-36.
29. Widmer, A. 2005. The Development of Güttingen-V-, Mikado and Drilling Growing Systems: An Overview. Obst- und Weinbau, 141(7): 14-16.
30. Widmer, A. and Krebs, C. 2001. Influence of Planting Density and Tree Form on Yield and Fruit Quality of ‘Golden Delicious’ and ‘Royal Gala’ Apples. Acta Hort., 557: 235-241.