On the interchange of alternating-amplitude pulsation cycles
  We characterized the time intervals between the interchanges of the alternating high- and low-amplitude extrema of three RV Tauri and three RR Lyrae stars. 
E. Plachy, L. Moln\'ar, Z. Koll\'ath, J. M. Benk\H{o} and K. Kolenberg
astro-ph.SR