TY - RPRT TI - CTFFIND4: Fast and accurate defocus estimation from electron micrographs AU - Alexis Rohou AU - Nikolaus Grigorieff PY - 2015 DO - 10.1101/020917 UR - https://www.biorxiv.org/content/10.1101/020917v1 ID - 10.1101/020917 ER -