I suggest you:

1. Eisenbud, Harris - The Geometry of Schemes, (2000) Springer Verlag, paragraph III.2.7;
2. Eisenbud, Harris - 3264 & All That, Intersection Theory in Algebraic Geometry, chapters 3 and 4 (click);
3. Görtz, Wedhorn - Algebraic Geometry I, (2010) Vieweg+Teubner Verlag, paragraphs from 8.4 to 8.10;
4. Kleiman S. L. - Geometry on Grassmannians and Applications to Splitting Bundles and Smoothing Cycles, Pubblications Mathématiques de l'I.H.É.S., 75 (1992) 5-95 (clack);
5. Vakil - FOAG (December 29 2015 version), paragraph 16.7 (clock).

I suggest you:

1. Eisenbud, Harris - The Geometry of Schemes, (2000) Springer Verlag, paragraph III.2.7;
2. Eisenbud, Harris - 3264 & All That, Intersection Theory in Algebraic Geometry, chapters 3 and 4 (click);
3. Görtz, Wedhorn - Algebraic Geometry I, (2010) Vieweg+Teubner Verlag, paragraphs from 8.4 to 8.10;
4. Kleiman S. L. - Geometry on Grassmannians and Applications to Splitting Bundles and Smoothing Cycles, Pubblications Mathématiques de l'I.H.É.S., 36 (1969) 281-297 (clack);
5. Vakil - FOAG (December 29 2015 version), paragraph 16.7 (clock).