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@@ -9,7 +9,7 @@ Exxon patent showing slot-style melt blowing nozzle: https://patents.google.com/
 
 UTenn study on melt blowing: https://onlinelibrary.wiley.com/doi/epdf/10.1002/pen.760302202
 
-good drawings: http://jmppnet.com/journals/jmpp/Vol_3_No_1_June_2015/9.pdf
+good discussion of primary air system requirements: http://jmppnet.com/journals/jmpp/Vol_3_No_1_June_2015/9.pdf
 
 ## melt blowing videos
 video of a polypropylene filter melt blowing line in action: https://www.youtube.com/watch?v=cGQ4piMNQ_E