Issel was a close correspondent with anthropologist Elio Modigliani, and helped promulgate his ideas.
Italian explorer Elio Modigliani visited Enggano Island between April 25 and July 13, 1891.
Amedeo Modigliani | Elio Vittorini | Elio Modigliani | Elio Di Rupo | Jeanne Modigliani | :it:Elio d'Anna | Franco Modigliani | Elio Sgreccia | Elio Roca | Elio Gustinetti | Elio Germano | Elio Gaspari | Elio D'Anna | Elio Cruz | Centro d'Arte Modigliani |
In his book "Toba na Sae; Sejarah lembaga sosial politik abad XIII-XX ( Jakarta: Komunitas Bambu, 2004) the Indonesian poet Sitor Situmorang describes the encounter between Guru Somalaing and Elio Modigliani who later wrote a book about his journeys into the independent Batak lands in his book "Fra i Batacchi indipendenti; Viaggio di Elio Modigliani" (1892 Roma: Società Geografica Italiana).