ENUM Validation Token Format Definition. - Otmar Lendl (RFC, 2007)

Combined User and Infrastructure ENUM in the e164.arpa Tree. - Michael Haberler; Otmar Lendl; Richard Stastny (RFC, 2009)

Cyber Attack Information Sharing. - Florian Skopik; Roman Fiedler; Otmar Lendl (Datenschutz und Datensicherheit, 2014)