The following are examples of data that were obtained from secondary
references, because the original references could not be, or were not,
obtained.  Copies of the original sources should be tracked down.  Short
of that, a consistent mechanism for citing both the original and the
scanned source should be used.  We should use the original sources whenever
possible, but hard-to-reach sources such as dissertations, technical
reports, and obscure meeting proceedings should be accompanied by an
easier to get secondary reference.

J.R. Biller, Ph.D. thesis, University of Illinois (1973)
 data used in
H.O. Barthel (74)

A.J. Crooker, (1969) "Phenomenological Investigation of Low Mode Marginal
Planar Detonations", University of Illinois Tech. Rep. FAE 69-2.
 data used in
J.H.S. Lee (77) - Initiation of Gaseous Detonation

Coulonnier - data labeled in plot but citation missing from bibliography.
 data used in
D. Desbordes and M. Vachon (1986), "Critical Diameter of Diffraction for
 Strong Plane Detonations"