21. Letter from Wilbur A. Sawyer to Margaret Sawyer

Date:

24 March 1942

22. Letter from Wilbur A. Sawyer to Margaret Sawyer

Date:

8 February 1941

23. Letter from Wilbur A. Sawyer to Margaret Sawyer

Date:

19 August 1940

24. Letter from Wilbur A. Sawyer to Margaret Sawyer

Date:

13 April 1940

25. Letter from Courtenay Crocker to Wilbur A. Sawyer

Date:

26 July 1939

26. Letter from Wilbur A. Sawyer to Courtenay Crocker

Date:

23 July 1939

27. Letter from Wilbur A. Sawyer to Margaret Sawyer

Date:

18 December 1937

28. Letter from Wilbur A. Sawyer to Margaret Sawyer

Date:

13 December 1937

29. Letter from Wilbur A. Sawyer to Margaret Sawyer

Date:

15 January 1937

30. The Distribution of Yellow Fever Immunity in North America, Central America, The West Indies, Europe, Asia, and Australia, with Special Reference to the Specificity of the Protection Test

Date:

1936