@book{Kierkegaard, author = {Kierkegaard, S{\o}ren}, title = {Fear and trembling and the sickness unto death, New York (Doubleday Anchor Books) 1954.}, language = {en} } @book{Kierkegaard, author = {Kierkegaard, S{\o}ren}, title = {Purity of heart is to will one thing, New York (Harper \& Brothers) 1956.}, language = {en} } @book{Kierkegaard, author = {Kierkegaard, S{\o}ren}, title = {Either / or. Volume one, New York (Anchor Books) 1959.}, language = {en} } @book{Kierkegaard, author = {Kierkegaard, S{\o}ren}, title = {Either / or. Volume two, New York (Anchor Books) 1959.}, language = {en} }