Take a cup of coffee and read the reviews of the german drum magazines:

PDF Sticks Ausgabe 05/2015
PDF drums & percussion Ausgabe 04/2015
PDF DrumHeads!! Ausgabe 04/2015

Daniel Jakobi is fan and buddy from the beginning: PDF Daniel Jakobi

Also in the web you can find some very nice articles.

Dave Kobrehel is a good author and shoots a lot of amazing videos:
http://www.jazzdrummerworld.com/drums-und-percussion-news/muffkopf-der-vintage-sound-fuer-die-bassdrum/#.VxCi93qRiSo
http://www.jazzdrummerworld.com/jazzdrummerworld/drum-workshops-material-fur-drummer/workshop-hip-hop-golden-era-grooves/#.VxCk23qRiSo

An english review by one of the biggest drum sites in the UK:
http://mikedolbear.com/story.asp?StoryID=4267

Right before the gaffer tape: the Muffkopf!
https://www.bonedo.de/artikel/einzelansicht/8-praktische-helfer-fuer-den-alltag-eines-drummers.html