Close binary companions of the HAeBe stars LkHα 198, Elias 1, HK Ori and V380 Ori K. W. Smith, Y. Y. Balega, W. J. Duschl, K.-H. Hofmann, R. Lachaume, T. Preibisch, D. Schertl and G. Weigelt A&A, 431 1 (2005) 307-319 Published online: 02 February 2005 DOI: 10.1051/0004-6361:20041135