1. Detection of π+π− atoms with the DIRAC spectrometer at CERN
2. B. Adeva, et al., First observation of πK atom and its lifetime measurement, CERN/SPSC 2000-032, SPS/P284, Add.2, Geneva, 2000.
3. DIRAC: A high resolution spectrometer for pionium detection
4. S. Vlachos, The drift distance trigger, DIRAC note 02-12, 2002 〈http://dirac.web.cern.ch/DIRAC/i_notes.html〉.
5. 〈http://garfield.web.cern.ch〉.