Spinal Cord Cells from Pre-metamorphic Stages Differentiate into Neurons and Promote Axon Growth and Regeneration after Transplantation into the Injured Spinal Cord of Non-regenerative Xenopus laevis FrogletsEmilio E. Méndez‐Olivos, Juan Larraı́n|Frontiers in Cellular Neuroscience|2017Cited by 18