Cumulative list of organizations, contributions to which are deductable under section 23 (o) and section 23 (q) of the Internal revenue code and the corresponding sections of prior revenue acts.

Mode of access: Internet.

The standard-operaglass : containing the detailed plots of ninety celebrated operas with critical remarks, dates &c. &c. /

Mode of access: Internet.

Engineering materials list : cumulative indexes /

"Subject Index for Supplements 13 through 26; Engineering Category Index for Supplements 1 through 26; Corporate Author Index for Supplements 13 through 26."

Engineering materials list : cumulative index /

"June 1968."

Engineering materials list : cumulative index /

"February 1969."

Engineering materials list : cumulative index 1968-1971 /

"March 1972."

Lessons from the Morrow Plots /

Cover title.

Estimating cumulative traffic loads.

"HRDI-13/03-05(600)E"--P. [4] of cover.