sageupstream http://files.sagemath.org//spkg/upstream/ https://ftp.riken.jp/sagemath/spkg/upstream/ https://www-ftp.lip6.fr/pub/math/sagemath/spkg/upstream ftp://ftp.fu-berlin.de/unix/misc/sage/spkg/upstream sagemath https://sage-on-gentoo.lipn.univ-paris13.fr/sage/