An H i line search for optically identified dwarf galaxy candidates in the M 81 groupW. van Driel, R. C. Kraan-Korteweg, B. Binggeli and W. K. HuchtmeierAstron. Astrophys. Suppl. Ser., 127 3 (1998) 397-408DOI: https://doi.org/10.1051/aas:1998108