en: The Pastaza River ( formerly known as Sumatara ) is a large tributary of the Marañón River in the northwestern Amazon - South American basin . The Pastaza River ( formerly known as the Sumatara ) is a large tributary to the Marañón River in the northwestern Amazon Basin of South America .
ms: Sungai Pastaza (dahulu dikenali sebagai Sumatara) adalah anak sungai besar Sungai Maran di barat laut Amazon-Asia Selatan lembangan. Sungai Pastaza (dahulu dikenali sebagai Sumatara) adalah anak sungai besar ke Sungai Maran di Lembangan Amazon barat laut Amerika Selatan.