Bibliographical sources mentioned in these texts:
Capitolinus, Julius 80.35; : Life of Clodius Albinus 80.9
Cranzius, Albertus 80.12, 80.36 : Saxonia 80.7
Deventer, Jacob van 80.4
Emmius, Ubbo Gretensis 80.22
Guicciardini, Ludovico 80.7
Kempius, Cornelius 80.22; Book on Friesland 80.12, 80.29
Olivarius, Petrus: Commentaries on Pomponius Mela 80.6, 80.30
Plinius 80.10, 80.35, 80.41; : Third chapter of the fifth book of his Natural History 80.18
Ptolemæus 80.3, 80.8, 80.12, 80.15, 80.34, 80.36
Saxo Grammaticus 80.12, 80.36
Strabo 80.19, 80.43
Suffridus Petrus Frisius : About the Frisians 80.22
Tacitus 80.2, 80.8, 80.9, 80.15, 80.16, 80.34, 80.35, 80.36, 80.38