Plank, Terry; Balzer, Vaughn; Carr, Michael J (2002): Nicaraguan volcanoes record paleoceanographic changes accompanying closure of the Panama gateway. Geology, 30, 1087-1090, doi:10.1130/0091-7613(2002)030<1087:NVRPCA>2.0.CO;2
References for data repository & four tables (URI: ftp://rock.geosociety.org/pub/reposit/2002/2002128.pdf)