At [1] the link in "see Introduction in Geiser User Manual" points to [2] but should link to [3].

[1] https://guix.gnu.org/manual/en/html_node/The-Perfect-Setup.html

[2] http://geiser.nongnu.org/Introduction.html#Introduction

[3] https://geiser.nongnu.org/geiser_1.html#Introduction