Bestvina, M., The topology of Out(Fn). Proceedings of the International Congress of Mathematicians, Vol. II (Beijing, 2002), 373–384, Higher Ed. Press, Beijing, 2002.
Bestvina, M., Geometry of Outer space, PCMI lectures 2012.
Bridson, M.R. and Vogtmann, K., Automorphism groups of free groups, surface groups and free abelian groups, in Problems on Mapping Class Groups, edited by B.Farb, Proc. Symposia in Pure Mathemaics, AMS, Providence, RI, 2006, 301-316.
Vogtmann, K.,, What is Outer space?, Notices of the AMS 55, No. 7 (2008) 784-786.
Vogtmann, K., Automorphisms of free groups and outer space, Proceedings of the Conference on Geometric and Combinatorial Group Theory, Part I (Haifa, 2000). Geom. Dedicata 94 (2002), 1–31.
Vogtmann, K., The cohomology of automorphism groups of free groups, Proceedings of the International Congress of Mathematicians, Madrid 2006, EMS, Zurich, Switzerland, 1101-1119.
Vogtmann, K.,On the geometry of Outer space, Bulletin of the AMS.
Original papers on outer space and train tracks
Bestvina, M. and Handel, M., Train tracks and automorphisms of free groups, Ann. of Math. (2) 135 (1992), no. 1, 1–51.
Culler, M. and Vogtmann, K., Moduli of graphs and automorphisms of free groups, (with M. Culler) Inventionnes 84 (1986), 91-119.
Classic references for automorphisms of free groups
Articles
D. Cooper, Automorphisms of free groups have finitely generated fixed point set,
J.Algebra 111 (1987), 453–456
W. Magnus, Uber n-dimensional Gittertransformationen, Acta Math. 64 (1934) 353-367.
J. McCool,
A presentation for the automorphism group of a free group of finite rank, J. London Math. Soc. (2) 8 (1974), 259-266.
J. Nielsen, Die isomorphismengruppe der freien Gruppen, Math. Ann. 91 (1924) 169-20).
J. R. Stallings, Topology of finite graphs, Invent. Math. 71 (1983), no. 3,
551{565.
W. P. Thurston, Minimal stretch maps between hyperbolic surfaces, arXiv:9801.039
J. H. C. Whitehead, On certain sets of elements in a free group, Proc. London
Math. Soc. 41 (1936) 48-56.
R. C. Lyndon and P. E. Schupp, Combinatorial Group Theory. Springer-
Verlag, Berlin, 1977
W. Magnus, A. Karass, A. and D. Solitar, Combinatorial Group Theory.
Wiley, New York, 1966
Other papers referred to during lectures
Stallings, John R. Topologically unrealizable automorphisms of free groups. Proc. Amer. Math. Soc. 84 (1982), no. 1, 21–24.
Krstić, Sava and McCool, James, The non-finite presentability of IA(F3 ) and GL2(Z[t,t-1]) Invent. Math. 129 (1997), no. 3, 595–606.
Zieschang, H , A note on the mapping class groups of surfaces and planar discontinuous groups. Low-dimensional topology (Chelwood Gate, 1982), 206–213,
London Math. Soc. Lecture Note Ser., 95, Cambridge Univ. Press, Cambridge, 1985.
Paulin, Frédéric, The Gromov topology on R-trees.Topology Appl. 32 (1989), no. 3, 197–221.
Hatcher, Allen, Homology stability for outer automorphisms of free groups. Comment. Math. Helv. 70 (1995), no. 1, 39–62.
Laudenbach, F,. Sur les 2-sphères d'une variété de dimension 3. Ann. of Math. (2) 97 (1973), 57–81
Hatcher, A., Homological stability for automorphism groups of free groups. Comment. Math. Helv. 70 (1995), no. 1, 39–62.
Brown, K. S., Cohomology of groups. Graduate Texts in Mathematics, 87. Springer-Verlag, New York-Berlin, 1982.
Vogtmann, K., Local structure of some Out(Fn)-complexes. Proc. Edinburgh Math. Soc. (2) 33 (1990), no. 3, 367–379.
Conant, J. and Vogtmann, K., Morita classes in the homology of Aut(F_n) vanish after one stabilization Groups Geom. Dyn. 2 (2008), no. 1, 121–138..
Kontsevich, M. Formal (non) commutative symplectic geometry. The Gelfand Mathematical Seminars, 1990–1992, 173–187.
Conant, J. and Vogtmann, K., On a theorem of Kontsevich, Algebr. Geom. Topol. 3 (2003) 1167-1224.