https://digitalcommons.usf.edu/kip_articles/2904/
"Iron Oxide-Rich Filaments: Possible Fossil Bacteria in Lechuguilla Cav" by Paula P. Provencio and...
Reddish filaments in two fragments of unusual iron oxide bearing stalactites, "the Rusticles" from Lechuguilla Cave, New Mexico, are found only within the...
https://pure.psu.edu/en/publications/biological-investigations-in-lechuguilla-cave/
Biological investigations in Lechuguilla Cave - Penn State
biologicalinvestigationscavepennstate