Sjölund, R. D. (1992) “Changes in Chloroplast Structure During Differentiation of Phloem Sieve Elements and Xylem Vessels from Green Callus Tissue of Streptanthus Tortuosus”, Acta Microscopica, 1(1), pp. 109-114. vailable at: https://acta-microscopica.org/acta/article/view/16 (ccessed: 3July2024).