These posters are nice – but truly “perfect” posters have been created by Josef Müller-Brockmann. If you compare these two designer’s work with intense detail, you will notice the difference in quality.
[...] Emil Ruder was a Swiss typographer (b. Zürich 1914, d. Basel, 1970), and type guru in the 50s and 60s. He Taught at the Basel School of Design (Kunstgewerbeschule), and founded the International Center for the Typographic Arts in New York, 1962. See more of his posters here. [...]