Twin directories of calc:

[DIR]  ftp://ftp.dit.upm.es/lotos/tools/TOPO_3R6/EPS_1R11/exs/expressions/calc/
[DIR]  ftp://ftp.linux.it/ubuntu/pool/universe/c/calc/
[DIR]  ftp://ftp.linux.it/debian/pool/main/c/calc/
[DIR]  ftp://134.121.1.1/.snapshot/nightly.3/pub/gnu/calc/
[DIR]  ftp://134.121.1.1/pub/gnu.OLD/calc/
[DIR]  ftp://134.121.1.1/.snapshot/nightly.2/pub/gnu/calc/
[DIR]  ftp://134.121.1.1/.snapshot/nightly.1/pub/gnu/calc/
[DIR]  ftp://134.121.1.1/.snapshot/nightly.0/pub/gnu/calc/
[DIR]  ftp://134.121.1.1/.snapshot/hourly.1/pub/gnu/calc/
[DIR]  ftp://ftp.cpsc.ucalgary.ca/pub/projects/charity/source/charity/work/Test/calc/
[DIR]  ftp://ftp.eutelia.it/pub/Sunsite_Mirror/apps/math/calc/
[DIR]  ftp://ftp.eutelia.it/pub/Info-Mac_Mirror/sci/calc/
[DIR]  ftp://ftp.cesca.es/mirror2/gnu/calc/
[DIR]  ftp://ftp.cesca.es/mirror/debian/pool/main/c/calc/
[DIR]  ftp://ftp.uni-frankfurt.de/pub/Mirrors3/debian.org/debian/pool/main/c/calc/
[DIR]  ftp://ftp.inf.utfsm.cl/pub/gnu/calc/
[DIR]  ftp://ftp.uni-magdeburg.de/pub/mirror/linux/debian/pool/main/c/calc/
[DIR]  ftp://aeneas.mit.edu/pub/gnu/calc/
[DIR]  ftp://debian.lcs.mit.edu/pub/debian-amd64/debian-amd64/pool/main/c/calc/
[DIR]  ftp://debian.lcs.mit.edu/info-mac/sci/calc/
[DIR]  ftp://debian.lcs.mit.edu/pub/debian-amd64/debian/pool/main/c/calc/
[DIR]  ftp://debian.lcs.mit.edu/debian/pool/main/c/calc/
[DIR]  ftp://ftp.kfki.hu/pub/linux/ubuntu/pool/universe/c/calc/
[DIR]  ftp://ftp.kfki.hu/pub/linux/ubuntu/pool/main/c/calc/
[DIR]  ftp://ftp.kfki.hu/pub/linux/debian/pool/main/c/calc/
[DIR]  ftp://ftp.internat.freebsd.org/pub/FreeBSD/ports/math/calc/
[DIR]  ftp://ftp.qrz.ru/pub/hamradio/calc/
[DIR]  ftp://ftp.skynet.be/mirror1/debian.org/pool/main/c/calc/
[DIR]  ftp://ftp.kreonet.re.kr/gnu/ibiblio/www/software/calc/
[DIR]  ftp://ftp.kreonet.re.kr/gnu/ibiblio/www/savannah-checkouts/gnu/www/software/calc/
[DIR]  ftp://ftp.kreonet.re.kr/gnu/ibiblio/ftp/gnu/calc/
[DIR]  ftp://ftp.prz.rzeszow.pl/pub/gentoo/portage/sci-mathematics/calc/
[DIR]  ftp://ftp.prz.rzeszow.pl/pub/gentoo/portage/app-emacs/calc/
[DIR]  ftp://ftp.prz.rzeszow.pl/pub/gentoo/portage/app-xemacs/calc/
[DIR]  ftp://ftp.prz.rzeszow.pl/pub/debian/pool/main/c/calc/
[DIR]  ftp://debian.lcs.mit.edu/hyperarchive/sci/calc/
[DIR]  ftp://ftp.cs.odu.edu/pub/zeil/cs711/calc/
[DIR]  ftp://ftp.3logic.net/.1/debian-archive/pool/main/c/calc/
[DIR]  ftp://ftp.3logic.net/.1/debian/pool/main/c/calc/
[DIR]  ftp://ftp.denet.dk/mirrors/ftp.simtel.net/pub/simtelnet/win3/calc/
[DIR]  ftp://ftp.denet.dk/mirrors/ftp.simtel.net/pub/simtelnet/winnt/calc/
[DIR]  ftp://ftp.denet.dk/mirrors/ftp.simtel.net/pub/simtelnet/winxp/calc/
[DIR]  ftp://ftp.denet.dk/mirrors/ftp.simtel.net/pub/simtelnet/handheld/handheld/calc/
[DIR]  ftp://ftp.sektornet.dk/mirrors/ftp.simtel.net/pub/simtelnet/win3/calc/
[DIR]  ftp://ftp.sektornet.dk/mirrors/ftp.simtel.net/pub/simtelnet/winnt/calc/
[DIR]  ftp://ftp.sektornet.dk/mirrors/ftp.simtel.net/pub/simtelnet/winxp/calc/
[DIR]  ftp://ftp.sektornet.dk/mirrors/ftp.simtel.net/pub/simtelnet/handheld/handheld/calc/
[DIR]  ftp://ftp.wustl.edu/pub/linux/distributions/debian/pool/main/c/calc/
[DIR]  ftp://ftp.darenet.dk/mirrors/ftp.simtel.net/pub/simtelnet/handheld/handheld/calc/
[DIR]  ftp://ftp.darenet.dk/mirrors/ftp.simtel.net/pub/simtelnet/win3/calc/