around 1920, Landeskirchliches Archiv Stuttgart

Curriculum vitae, 1929; instructions and vows of secondment, 1930; correspondence and reports (also during internment), 1928-1970; travelogue, 1930; monthly reports, 1932-1940; map of Kijunja, drawn by Martha Söhlke, 1932; language exams and reports. Martha Söhlke assessed by W. Hosbach, 1932; reports from various African hospitals, including Stellenbosch in South-West Africa, 1948-1949; reports from work at Missionshospital Witzieshoek in South Africa, 1949-1967; medical findings, 1957

Curriculum vitae, 1928; instructions and vows of deputation, 1929; correspondence during her internment and later at home, 1927-1967; mission reports, 1929-1939; annual report Kijunja, 1932; circulars to godparents and friends of Haya girls, 1933-1939

Letters, circulars, reports from Bukoba and Kijunja by Maria Fröhlich, 1929-1935; circulars by W. Hosbach, Brothers and Sisters number 1-7 by H. Scholten, 1934; letter by Christiane Blasyo Kashasha, 1934; letter by Josua Hermas, 1934; letters and cards by Martha and Wilhelm Hosbach, 1949-1958