By Audet, Richard, Ludwig, Gail
By Ludwig, Ralf
By O. Brennan, Patricia, G. Yassa, Janet, Ludwig, Stephen, McQueen, Alisa, Paik, S. Margaret
By Bemelmans, Ludwig
By Bemelmans, Ludwig, Bemelmans, Ludwig
By Feuerbach, Ludwig
By Prandtl, Ludwig, Tietjens, O.G., Rosenhead, L.
By Ludwig, Thomas
By Goldscheider, Ludwig, Story, Sommerville
By Wittgenstein, Ludwig
By Wittgenstein, Ludwig, Anscombe, G. E. M., von Wright, G. H., Paul, Denis