European swallows Hirundo rustica in Botswana / ed. by Bennie van den Brink, Rob G. Bijlsma and Tom M. van der Have ; [maps and fig.: Rob G. Bijlsma ... et al. ; photogr.: Bennie van den Brink]European songbirds and barn swallows Hirundo rustica in Ghana : a quest for constant effort sites and swallow roosts in December/January 1996/97 / eds.: Bennie van den Brink, Rob G. Bijlsma, Tom van der Have ; [figures Rob Bijlsma ... et al.]