TITLE: Reference Request for Fibre Bundle Theory from the Smooth Manifold Point of View
QUESTION [6 upvotes]: I am looking for a book, or a set of notes, which discusses some basic theory of fibre bundles. I am interested more in the geometric aspect (smooth manifolds) rather than topological aspect.
I found Steenrod's Topology of Fiber Bundles which covers the topology part in quite some depth but nothing which discusses the smooth aspect.
Can anybody point me to a nice source?

REPLY [4 votes]: You can consult:

Husemöller - Fibre Bundles;
Koszul - Lectures On Fibre Bundles and Differential Geometry, available at http://www.math.tifr.res.in/~publ/ln/tifr20.pdf;
Spivak - A Comprehensive Introduction to Differential Geometry, only volumes 1 and 2.

And if you are sufficiently experienced, you can consult:

Kobayashi, Nomizu - Foundations of Differential Geometry, both two volumes;
Kolár, Michor, Slovák - Natural Operations in  Differential Geometry, available at http://www.emis.de/monographs/KSM/kmsbookh.pdf;
Milnor, Stasheef - Characteristic classes, a very easy text but very deep!