1. Alakukku, L., Perälä, P., Regina, K., 2007. Structure of mouldboard ploughed and zero tilled topsoil. Land-Technik AgEng 2007. Engineering solutions for energy and food production. In: Conference: Agricultural Engineering, Hanover, November 09–10, 2007.VDI-Berichte Nr. 2001, pp. 483–487.
2. Alakukku, L., Ristolainen, A., Salo, T., 2009. Grain yield and nutrient balance of spring cereals in different tillage systems. In: Proceedings of ISTRO 18th Triennial Conference ‘Sustainable Agriculture’, June 15–19, 2009, Izmir, Turkey. CD-ROM. T6-005-1-T6-005-7.
3. Barley, canola, and weed growth with decreasing tillage in a cold, semiarid climate;Arshad;Agron. J.,1995
4. Effects of shallow tillage on physical properties of clay soil and growth of spring cereals in dry and moist summers in southern Finland;Aura;Soil Till. Res.,1999
5. Response of corn to small amounts of fertilizer placed with the seed: II. Summary of 22 field trials;Bates;Agron. J.,1971