@article {Pietrzyk2011, author = {Uwe Pietrzyk and Karl Herholz and Gereon Fink and Andreas Jacobs and R{\"u}diger Mielke and Ina Slansky and Michael W{\"u}rker and Wolf-Dieter Heiss}, title = {An Interactive Technique for Three-Dimensional Image Registration: Validation for PET, SPECT, MRI and CT Brain Studies}, volume = {35}, number = {12}, pages = {2011--2018}, year = {1994}, publisher = {Society of Nuclear Medicine}, issn = {0161-5505}, URL = {https://jnm.snmjournals.org/content/35/12/2011}, eprint = {https://jnm.snmjournals.org/content/35/12/2011.full.pdf}, journal = {Journal of Nuclear Medicine} }