Readers should cite both the Bio-protocol preprint and the original research article where this protocol was used:

Kanaya, H, Kobayakawa, Y and Itoh, T(2021). Whole-mount in situ hybridization of Hydra. Bio-protocol Preprint. bio-protocol.org/prep777.
Kanaya, H. J., Park, S., Kim, J., Kusumi, J., Krenenou, S., Sawatari, E., Sato, A., Lee, J., Bang, H., Kobayakawa, Y., Lim, C. and Itoh, T. Q.(2020). A sleep-like state in Hydra unravels conserved sleep mechanisms during the evolutionary development of the central nervous system . Science Advances 6(41). DOI: 10.1126/sciadv.abb9415