There is a saying "Do you read the masters?"


I want to read some basic papers in Topology/geometry...


I can not clearly state what is basic as of now...


My back ground includes course in 


* Category theory, Some group Cohomology
* Algebraic topology
* Differential forms, deRham cohomology
* Representation theory of finite groups
* Lie groups and Lie algebras


I am interested to learn some $K$ theory.


The reason I am interested is I did a course in representation theory(from Serre's Book).. In that there is a discussion about Grothendick group ... We denote it by $K(\mathcal{F})$.. Though i do not understand it it was fascinating... Then I saw that this $K$ is the $K$ in $K$- theory... 


I was reading some smooth manifolds and came across with what is called tangent bundle, vector bundle, fibre bundle.. Then realized this fibre bundle has some thing to do with fibrations and vector bundles are related to $K$- theory...


So, all that i want to ask is a suggestion about the papers that i can read with this background. 


PS : I believe this can be made to community wiki at least. This is a question that asks to refer some books and i have given details. 



research articles in topology/geometry
It is worth noting that in $K$-theory one can read `the masters' without that necessarily meaning reading research papers. Specifically, if you are interested in topological $K$-theory, then [Atiyah's book](http://www.amazon.co.uk/K-theory-Advanced-Classics-Michael-Atiyah/dp/0201407922/ref=sr_1_1?ie=UTF8&qid=1454877913&sr=8-1&keywords=atiyah+k+theory) is still a very good introduction. Similarly, [Milnor's book](http://www.amazon.co.uk/Introduction-Algebraic-K-Theory-Mathematics-Studies/dp/0691081018/ref=sr_1_1?ie=UTF8&qid=1454877975&sr=8-1&keywords=milnor+k+theory) is an excellent introduction to the lower algebraic $K$-groups.


