Pācīna Suttā. A group of three suttas, in all of which it is stated that just as certain rivers (e.g. Gangā, Yamunā, Aciravatī, etc.) tend to flow eastward, so the monk who cultivates the Noble Eightfold Path tends to Nibbāna. S.v.38f.

Dictionary of Pali Proper Names, G P Malalasekera (1899-1973), which is available as printed version from