Recording Simultaneously [n: Or Selectively] By Methods Covered By Different Main Groups [n: Among G9b/3, G9b/5, G9b/7 And G9b/9]; Record Carriers Therefor [n: Not Otherwise Provided For]; Reproducing Therefrom [n: Not Otherwise Provided For (g9b/9.001 And G9b/11.001 Take Precedence; Driving Or Moving Of Heads G9b/3.008, G9b/5.147, G9b/7.041 And G9b/21.003)] {g11b 13/00} Patents (Class G9B/13)