<< Matter known as ordinary, which makes up everything we know, corresponds to only 5% of the Universe. >>
<< (..) the majority of the missing ordinary matter is found in the form of a very hot gas associated with intergalactic filaments >>
http://www.alphagalileo.org/ViewItem.aspx?ItemId=158939&CultureCode=en
Dominique Eckert, Mathilde Jauzac, et al. Warm–hot baryons comprise 5–10 per cent of filaments in the cosmic web. Nature, 2015; 528 (7580): 105 DOI: 10.1038/nature16058
http://www.nature.com/nature/journal/v528/n7580/full/nature16058.html