Polish Society of Nephrology improvements in continuous professional development as well as research activities among young doctors and other professionals in the fields of nephrology, dialysis therapy and renal transplantation. PSN Congresses are organized every three years. As yet twelve Congresses were held in the following locations in Poland: 1st Congress - Bydgoszcz (1983) 2nd Congress - Kraków (1986) 3rd Congress - Gdańsk (1989) 4th Congress - Katowice (1992) 5th Congress - Lublin (1995) 6th Congress - Poznań (1998) 7th Congress - Kraków (2001) 8th Congress - Białystok (2004) 9th Congress – Katowice/Wisła (2007) 10th Congress - Bydgoszcz (2010) 11th Congress - Wrocław (2013)
Four Organs work, each tone sounds almost in sequence. A continuous maraca beat serves as a rhythmic framework. Reich describes the piece as "the longest V–I cadence in the history of Western Music," the V and I chords being contained within the one chord. "You'll find the chord in Debussy and Thelonious Monk – the tonic on top and the dominant on the bottom." He has cited the music of Pérotin and other twelfth and thirteenth century composers as suggesting the technique of note augmentation used in "Four Organs". For performances of the piece, Reich recommended using electronic organs with as plain