From Tennyson, et al.
This and the next slide pertain to this geometry.
Relevant papers are unknown to the writer. Perhaps the following is relevant:
R. C. Tennyson, "Advances in Shell Buckling -Theory and Experiments," in "Developments in Engineering Mechanics," Canadian Society for Civil Engineering, Commemorative Centennial Volume, Elsevier Science P.V., Amsterdam, The Netherlands, 1987
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