TY  - RPRT
TI  - An improved phase-contrast microscope with variable amplitude and phase difference.
AU  - B O PAYNE
PY  - 1954
DO  - 10.1111/j.1365-2818.1954.tb02008.x
UR  - https://pubmed.ncbi.nlm.nih.gov/13212798/
ID  - 13212798
ER  -