Welcome to the Registry of Open Access Repositories - Registry of Open Access Repositories. NDLTD: Networked Digital Library of Theses and Dissertations ? NDLTD. NDLTD: Networked Digital Library of Theses and Dissertations ? NDLTD. Cybertesis.NET - Portal de Tesis. Red de Revistas Cientificas de América Latina y el Caribe, España y Portugal.