Thomas Barthel's "Grundlagen zur Entzifferung der Osterinselschrift", published in 1958 in Hamburg by Cram, de Gruyter, contains the most reliable, faithful, and comprehensive reproductions of the rongorongo corpus.

• Reliable.      There are few errors. The Rongorongo Commission of the Cercle d'Études sur l'Île de Pâques et la Polynésie estimates that about one sign in 30 is erroneous. See example.
• Faithful.      The drawings, tracings made from rubbings, are more faithful to the originals than freehand copies. Compare with Fischer 1997.
• Comprehensive.      Slightly more than 99% of the corpus is represented. The drawings cover objects A to X, approximately 13900 signs. Missing are the 120 signs or so on the Snuff Box (Y), the authenticity of which is disputed, and on the Poike Tablet (Z), which is in poor condition.