Kaj Holmberg and Ragnar Olsson
Vidensk. Meddr. dansk naturh. Foren. (1984) 145:43—52 (no DOI found)
The origin of Reissner's fibre in an appendicularian, Oikopleura dioica
The Reissner's fiber in O. dioica is produced by a single ”fibrogen” cell. Electron microsocopy of this cell show a large perikaryon, cisternas, and a single cilium, which is inserted in the central canal.