TY  - RPRT
TI  - Circular of the Bureau of Standards no. 402: sundials
AU  - Gould, Ralph Edgar
PY  - 1933
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS CIRC 402
DO  - 10.6028/NBS.CIRC.402
ER  -