I am currently reading Great Circle Fibrations of the Three-Sphere by Gluck and Warner since I am very interested in the Hopf-fibration. In particular I'm looking for properties which make it special, so this caught my eye.
In the introduction, the authors remark that
Any fibration of $S^3$ by simple closed curves must have base space a two-sphere and, as is well known [S], must be equivalent to the Hopf-fibration.
Sadly, the reference, Steenrod's The Topology of Fibre Bundles, isn't available through my university library or any of its partners.
Since this is "well known", I was hoping that someone could perhaps outline a proof, reference a theorem/construct which can be used to prove this fact, or another source in which a proof could be found.
