Typology of modifications to peer support work for adults with mental health problems: systematic review. - Charles, Ashleigh; Thompson, Dean; Nixdorf, Rebecca; Ryan, Grace; Shamba, Donat; Kalha, Jasmine; Moran, Galia; Hiltensperger, Ramona; Mahlke, Candelaria; Puschner, Bernd; Repper, Julie; Slade, Mike; et al. (British Journal of Psychiatry, 2020)