@book{52721,
	author = {Mortensen, Theodor, and Carlsbergfondet (Copenhagen, Denmark)},
	title = {A monograph of the Echinoidea.},
	publisher = {C. A. Reitzel,},
	year = {1928-},
	address = {Copenhagn,},
	note = {Published at the expense of the Carlsberg-fund.}
}