Cite
MLA Citation
British Standards Institution,. Guide to construction and use of 90 mm (3.5 in) flexible disk cartridges for data interchange, using modified frequency modulationrecording at 7958 ftprad, 5.3 tpmm (135 tpi) on 80 tracks on each side.. London : British Standards Institution, 1988. http://access.bl.uk/ark:/81055/vdc_100103920830.0x000001