For ecology see: i) Ecology and applications of benthic foraminifera by Murray, 2006, which gives information about several foraminiferal species, and

ii) Gupta & Barun (1999) Modern foraminifera.

In terms of taxonomy: i) Jones (1994) - The Challenger foraminifera and ii) Holbourn et al. (2013) - Atlas of benthic foraminifera.

All of these are books.

Hope that helps a bit