411 REFERENCE · Wikibooks
Chess Opening Theory/1. d4/1...d5/2. c4/2...e6/3. Nc3/3...Nf6/4. Nf3/4...Be7/5. Bf4/5...O-O/6. e3/6...c5/7. dxc5/7...Bxc5/8. Qc2/8...Nc6
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
Queen’s Gambit Declined, Blackburne Variation, Main Line
8...Nc6
Black simply develops. White continues with 9. a3, an important move to control b4 and prepare b2-b4.