5.April 1975
http://wetterforum.info/showthread.php?t=15489
6.April 1975
http://wetterforum.info/showthread.php?t=15496
7.April 1975
http://wetterforum.info/showthread.php?t=15502
9.April 1975
http://wetterforum.info/showthread.php?t=15511
10.April 1975
http://wetterforum.info/showthread.php?t=15520
11.April 1975
http://wetterforum.info/showthread.php?t=15531