https://arxiv.org/abs/1704.02704
[1704.02704] POLOCALC: a Novel Method to Measure the Absolute Polarization Orientation of the...
Abstract page for arXiv paper 1704.02704: POLOCALC: a Novel Method to Measure the Absolute Polarization Orientation of the Cosmic Microwave Background
https://digitalcollections.syr.edu/Documents/Detail/american-book-company-production-plate-02704-learning-to-subtract/26342
American Book Company Production Plate 02704: Learning to subtract - Syracuse University Libraries...
American Book Company Production Plate 02704: Learning to subtract, 1801-1971, Publisher's production plates, Figures (illustrations), English, American Book...