Anon. 1984. Official Methods of Analysis. 17th Ed. In: Horwits, W. (Ed). Association of Afficial Analytical Chemists (A.O.A.C). Washington. D. C.
Castro, C. A. 1988. Effect of nitrogen and patassium fertilizers on yield & quality of two potato cultivars. Anais-da-UTAD. 1(1): 117-123.
Chadchan, R. and Biradar, D. P. 1989. Impact of plant population & nitrogen levels on storage of potato tubers of different grands. Karnataka J. Agric. Sci. 2(4):325-328.
Chris, M., Long, C. M., Snapp, S. S., Douches, D. S. and Chase, R. W. 2004. Tuber yield, storability, and quality of Michigan cultivars in response to nitrogen management and seedpiece spacing. American J. Potato Res. 81(5): 347-357.
Cogo, C. M., Andriolo, J. L., Dilson, A. B. and Bortolotto, O. C. 2006. Growth, yield and chip color of potato tubers grown under high potassium availability. Ciência Rural Cienc. Rural. 36(3).
Hassandokht, M., Kashi, A. and Hamedi, M. 1998. Study of the effect of manor and N fertilizer on quantitative and qualitative potato traits. Proceedings of the 5th congress of agronomy and plant breeding. Karaj. Iran. (in Farsi)
Kholdebarin, B. and Isslamzadeh, T. 2001. Mineral nutrition of high plants. University of Shiraz Pub. Shiraz. Iran. (in Farsi).
Kleinkopf, G. E., Westerman, D. T. and Welle, R. B. D. 1981. Dry matter production and nitrogen utilization by potato cultivars. Agron. J. 73(2):799-802.
Kolbe, H. and Hipp, J. 1995. Relations between N, P & K concentrations at harvest time and changes in weight loss and chemical composition of potato tubers during long-term storage at 4°C. Agribiol. Res. 48(1):14-25.
Maghrour, J. 1998. Effect of different amount of nitrogen on dry matter of potato. Proceedings of the 5th congress of agronomy and plant breeding. Karaj. Iran. (in Farsi)
Mishra, S., Sinha, V. P. and Sharma, H. M. 1990. Quality studies in sweet potato cultivars in relation to nitrogen fertilization. J. Roof crops. 16 (2): 142-144.
Rezaee, A. and Soltani, A. 1996. Introduction to potato production. University of Mashhad Pub. Mashhad. Iran. (in Farsi)
Rogozinska, L. 1993. Changes in quality and storage ability of potato tubers grown on very light soil as affected by sprinkling and N fertilizing. Postepy. Nauk. Rolniczych. 45(1): 83-90
Roumizadeh, S. 1998. N fertilizer recommendation according to soil testing. Proceedings of the 5th congress of agronomy and plant breeding. Karaj. Iran. (in Farsi)
Salardini, A. and Mojtahhedi, M. 1993. Principles of plant nutrition. University of Tehran Pub. Tehran. Iran. (in Farsi)
Zhang, W. and Zang, W. L. 1995. Model calculations for the effect of N, P, K nutrition on behavior of potato tubers in storage. Potato Res. 38(1): 87-97.
)