APA

Walker G., . (2004). Modern Competetive Strategy. Boston: McGraw-Hill. Irwin.

Chicago

Walker G, . 2004. Modern Competetive Strategy. Boston: McGraw-Hill. Irwin.

Harvard

Walker G., . (2004). Modern Competetive Strategy. Boston: McGraw-Hill. Irwin.

MLA

Walker G, . Modern Competetive Strategy. Boston: McGraw-Hill. Irwin. 2004.