1. A multipurpose vacuum seed planter for vegetable crops plantings;Chen;Journal of Agriculture and Forestry,1993
2. Hanacek WA; et al. (1984). United States Patent. Patent No. 4,466,554
3. Development and test of magnetic precision seeder for plug seedlings;Hu;Transactions of Chinese Society of Agricultural Engineering,2003
4. Development of vacuum nozzle seeder for cucuribitaceous seeds (I)—design factors for vacuum seeding large sized seeds;Kim;Journal of the Korean Society for Agricultural Machinery,2003
5. A planting template for plug flats;Marr;Horticultural Technology,1991