1. Adem HH, Tisdall JM, Uren NC (1990) Setting standards for soil physical properties which affect germination and emergence of wheat Triticum aestivum. In: Australian society of soil science tetra-branch conference, Bendigo Australia, pp 98–102
2. Anon (1975) MAFF, experimental development report, ADAS. E. Region 1975–78. In: Allan HP (ed.) (1981) Direct drilling and reduced cultivations. Farming Press Ltd., Ipswich
3. Ashworth M (2007) Dedicated to discs: what do disc openers need to provide for optimum seed germination? WANTFA New Front 15(5):135–137
4. Baker CJ, Mai TV (1982a) Physical effects of direct drilling equipment on undisturbed soils. IV. Techniques for measuring soil compaction in the vicinity of drilled grooves. NZ J Agric Res 25:43–49
5. Baker CJ, Mai TV (1982b) Physical effects of direct drilling equipment on undisturbed soils, V. Groove compaction and seedling root development. NZ J Agric Res 25:51–60