Lewis, Celesta( 2004) Keeping Key Staff, AIA Handbook 2004 book Tillich, Paul: Gesammelte Werke. Erganzungs- und Nachlabande: Berliner Vorlesungen III. (1951-1958), pp 91-100. checking the Professional Service Manual Of Seamanship, pp 143-205. tactical , pp 56-74, 105-14. AIA Handbook, Chapter 9: 221-54.