Changes in serotonin levels, N-acetyltransferase activity, hydroxyindole-O-methyltransferase activity, and melatonin levels in the pineal gland of the Richardson's ground squirrel in relation to the light-dark cycle

1. Reiter, R.J.
2. Hurlbut, E.C.
3. Esquifino, A.I.
4. Champney, T.H.
5. Steger, R.W.