Twin directories of 1991:

[DIR]  ftp://ftp.cs.rutgers.edu/pub/hirsh/papers/1991/
[DIR]  ftp://ftp.ips.gov.au/wdc-data/spec/spectrograph event logs/culgoora/1991/
[DIR]  ftp://ftp.ips.gov.au/wdc-data/riometer/data/maw/1991/
[DIR]  ftp://ftp.ips.gov.au/wdc-data/riometer/data/mcq/1991/
[DIR]  ftp://ftp.ips.gov.au/wdc-data/solradio/data/learmonth/LSR/1991/
[DIR]  ftp://ftp.ips.gov.au/wdc-data/riometer/data/cas/1991/
[DIR]  ftp://ftp.ips.gov.au/wdc-data/riometer/data/dav/1991/
[DIR]  ftp://ftp.ips.gov.au/data/Products and Services/Monthly Reports/1991/
[DIR]  ftp://ftp.psg.com/pub/lists/1991/
[DIR]  ftp://ftp.niwa.co.nz/tropac/co2/bhd/1991/
[DIR]  ftp://ftp.ripe.net/ripe/tools/bind/mail-archive/1991/
[DIR]  ftp://ftp.iszf.irk.ru/ssrt/bursts/1991/
[DIR]  ftp://ftp.kreonet.re.kr/Mozilla/mozilla.org/addons/1991/
[DIR]  ftp://ftp.cs.wisc.edu/pub/techreports/1991/
[DIR]  ftp://ftp.cs.washington.edu/tr/1991/
[DIR]  ftp://ftp.3logic.net/pub/fidonet/nodelist/1991/
[DIR]  ftp://ftp.dur.ac.uk/pub/comp-sci/tech-reports/1991/
[DIR]  ftp://ftp.hitl.washington.edu/pub/scivw/conferences/1991/
[DIR]  ftp://ftp.hitl.washington.edu/pub/scivw/postings/1991/
[DIR]  ftp://ftp.stsci.edu/pub/stsci/newsletters/1991/
[DIR]  ftp://ftp.diku.dk/diku/reports/1991/
[DIR]  ftp://ftp.diku.dk/diku/semantics/conferences/1991/
[DIR]  ftp://ftp.tnt.uni-hannover.de/pub/papers/1991/
[DIR]  ftp://ftp.uni-stuttgart.de/pub/systems/acorn/riscos/ftp.acorn.co.uk/documents/acornusr/1991/
[DIR]  ftp://ftp.uni-hannover.de/pub/mirror/mozilla/addons/1991/
[DIR]  ftp://ftp.cs.iastate.edu/pub/tech_reports/1991/
[DIR]  ftp://ftp.cs.technion.ac.il/pub/Tech_Reports/1991/
[DIR]  ftp://ftp.cs.kuleuven.be/pub/Ada-Belgium/mirrors/pal/ajpo/news/quarterly/1991/
[DIR]  ftp://ftp.amigascne.org/mirrors/ftp.modland.com/pub/documents/nostalgia/magazine scans/DMZ/1991/
[DIR]  ftp://ftp.uni-koeln.de/misc/unix-world/ans2unix/1991/
[DIR]  ftp://ftp.uni-koeln.de/misc/unix-world/grabbag/1991/
[DIR]  ftp://ftp.uni-koeln.de/misc/unix-world/tutorial/1991/
[DIR]  ftp://ftp.cs.york.ac.uk/.snapshot/weekly.2/pub/arch/neural/publications/1991/
[DIR]  ftp://ftp.cs.ubc.ca/local/techreports/1991/
[DIR]  ftp://ftp.wh2.tu-dresden.de/pub/mirrors/browser/mozilla/addons/1991/
[DIR]  ftp://ftp.cs.york.ac.uk/.snapshot/weekly.0/pub/arch/neural/publications/1991/
[DIR]  ftp://ftp.cs.york.ac.uk/.snapshot/weekly.3/pub/arch/neural/publications/1991/
[DIR]  ftp://ftp.cs.york.ac.uk/pub/arch/neural/publications/1991/
[DIR]  ftp://ftp.fas.sfu.ca/pub/cs/TH/1991/
[DIR]  ftp://ftp.fas.sfu.ca/pub/cs/TR/1991/
[DIR]  ftp://ftp.bls.gov/pub/special.requests/ce/aggregate/1991/
[DIR]  ftp://ftp.bls.gov/pub/special.requests/ce/Share/1991/
[DIR]  ftp://ftp.bls.gov/pub/special.requests/cew/1991/
[DIR]  ftp://ftp.bls.gov/pub/special.requests/ce/standard/1991/
[DIR]  ftp://ftp.cs.utk.edu/pub/TechReports/1991/
[DIR]  ftp://ftp.cs.albany.edu/pub/tech-reports/1991/
[DIR]  ftp://ftp.anu.edu.au/mnt/disk3/sun-info/sunflash/1991/
[DIR]  ftp://ftp.anu.edu.au/mnt/disk3/Asia/Indo/txt/Cukilan/1991/
[DIR]  ftp://ftp.anu.edu.au/mnt/disk3/Asia/Indo/txt/Economica/1991/
[DIR]  ftp://ftp.anu.edu.au/mnt/disk3/Asia/Indo/txt/MasyIndon/1991/