 These songs were considered in a 1964 musicological publication, with a selection of the songs published in 2000 as "Songs of Tuvalu" together with two CDs of the recorded songs.He returned to the Ellice Islands, where he showed the films he made on his previous visit and made further film documentaries.Koch then carried out research continued on the Gilbert Islands, and in 1965 he published a book on the material culture of the Glbert Islands.