Sun, J., Niu, Q. W., Tarkowski, P., Zheng, B., Tarkowská, D., Sandberg, G., Chua, N. H., Zuo, J. The Arabidopsis AtIPT8/PGA22 gene encodes an isopentenyl transferase that is involved in de novo cytokinin biosynthesis. Plant Physiology. 2003, 131(1), 167-176. ISSN 0032-0889. E-ISSN 1532-2548.