| Niewier: Abdij Syon |
Abdij Syon or O.L.V. ten Dale; cistercian nun's monastery, founded between 1165 and 1195, at Niewier (Frisia).
NL-DHk Depot KNAW, 34, Ordinal in vernacular, 1561
 | Monasticon Batavum 3, pp. 85-86 |
| | W.M. Brada: Klooster Sion Niawier (Leusden 1988) |
| Zie ook AAU, XXIX, 1903, 138 |