The August 2005 Chess Life (which arrived today) contains an article by GM Susan Polgar on the "Urusoff Gambit" (1.e4 e5 2.Bc4 Nf6 3.d4), pp. 36-37. The article offers a fairly good introduction to the line and its themes--probably more than we should expect from a two-page piece. But, like most chess publications, there is no bibliography of sources nor recommendations for further reading. Perhaps GM Polgar and her able assistant FM Paul Truong can include online supplements at their blog or website to accompany future articles. In the meantime, here is my own contribution on the Urusov bibliography, to which I've contributed a thing or two.
BTW: Most current writers in English, of course, spell it "Urusov," following the lead of Tim Harding, but I suppose that "Urusoff" makes sense on the model of "Petroff" (which is generally preferred over "Petrov"). Gary Lane also prefers "Urusoff," for example. And at least Polgar didn't spell it "Ourousoff" or some equally ridiculous way.
The following sources are the most current or those most easily accessed on the web. They are not listed alphabetically but in order of usefulness and/or accessibility. Each is followed by a brief assessment or annotation. A more complete bibliography can be found in the Acknolwedgments to my Urusov Gambit pages.
Goeller, Michael. The Urusov Gambit System, The Urusov Gambit, and the Dimock Theme Tournament. Available online.
This is a complete analysis of the gambit, covering all major lines and offering some treatment also of the Two Knights Defense and other Bishop's Opening lines if Black avoids the gambit. I have not updated the analysis in at least a year and a number of good sources have appeared since (see below). Beginning players looking for a fun introduction to the gambit might most enjoy the games from the Dimock Theme Tournament, which I have annotated rather deeply.
__________. Goeller-Mazzillo, Kenilworth Chess Club Championship 2005. Annotated at the Kenilworth Chess Club site and available in various formats.
Harding, Tim. Bishop's Opening. The Chess Player 1973.
This is a bit old now and likely unavailable. If I remember right (I don't have it handy) he calls it the "Ourousoff" here. The articles below, all available online, offer much better coverage and improved analysis.
__________. "Once more unto the Urusov, dear friends, once more..." The Kibitzer #83 at ChessCafe. April 2003.
This is probably Harding's most thorough review of the gambit to date. It includes several important games with his annotations, plus a useful critique of and addition to my own analysis (some of which I have incorporated or responded to).
__________. "Interesting Byways in the Classic Open Games." The Kibitzer #46 at ChessCafe. 2000.
__________. "Some Opening Topics Revisited." The Kibitzer #33 at ChessCafe. 1999.
__________. "Is the Urusov Gambit Sound?" The Kibitzer #29 at ChessCafe. 1998.
__________. "The Eternal Appeal of the Urusov Gambit." The Kibitzer #28 at ChessCafe. 1998.
__________. "What Exactly Is the Bishop's Opening?" The Kibitzer #27 at ChessCafe. 1998.
Lane, Gary. The Bishop's Opening Explained. Batsford 2004.
Pages 28-41 of this recent book offer excellent coverage not only of the Urusoff gambit but of the Modern Variation of the Two Knights Defense (1.e4 e5 2.Bc4 Nf6 3.d4 exd4 4.Nf3 Nc6 5.e5 or various other transpositions), which is likely the best method of meeting 4...Nc6. Lane also does a better job of my site of laying out an entire Bishop's Opening repertoire, covering all the major transpositions. This is an excellent book, especially for lower-rated players since it does such a great job of covering the lines and discussing themes. Lane also focuses on recent games which have often not been discussed elsewhere.
__________. "Five Pawns Attack." Opening Lanes #26 at ChessCafe. 2001.
__________. Winning with the Bishop's Opening. Henry Holt 1993.
I think that anything of value related to the Urusoff in this book has been adapted into either Lane's more recent book or my website.
Müller, Karsten and Martin Voigt. Danish Dynamite: Explosive Gambits: the Danish, Goring, Scotch, and Urusov. Millford, CT: Russell Enterprises, 2003.
Muller and Voigt offer by far the best recent analysis of the Urusov Gambit on pp. 206-223 of their book, though various transpositions are covered throughout and are worth knowing. As the book is written in Informant-style notation, it offers some deep coverage of lines. In some cases, they carry the analysis quite deep but in others they leave it as "unclear" or "with compensation," and I wish they had pushed forward a bit more. But that would be my only criticism of this wonderful effort.
Schiller, Eric. White to Play 1.e4 and Win. Chess Digest, 1992.
I recommend this with caveats galore (for which you can see my recent game and analysis mentioned above), especially as regards the errors in his analysis, but I like some of Schiller's discussion. I also think the overall repertoire he offers fits well with the Urusov in many cases, and the book is therefore worth knowing for that alone.
Anonymous. Le Gambit Urusov from the Mjae website
This is mostly a French plagiarism of my own writings, but they do a fairly good job of simplifying my lines while offering good general coverage. And at least they give me some acknowledgment. FYI: The picture they have of "Prince Urusov" is actually a relative of his and not the man himself.
Fingerhut, Armin. Das Urusow-Gambit Available online.
Rather dense analysis of the main lines, and based on some older sources. But it is easily available, so I mention it.
Tartakower, Dr. S. and J. Du Mont. 100 Master Games of Modern Chess. Dover 1975.
I mention this because it is probably on your shelf or the shelf of your public library. It contains analysis of Heikenheimo-Crepaux, Dubrovnik 1950, which is the focus of the French plagiarists too.
Van der Tak, A. C. "A Forgotten Gambit." New In Chess Yearbook. Volume 59. Edited by Genna Sosonko and Paul van der Sterren. Netherlands: Interchess BV 2001. 106-111.
Good discussion of relatively recent games, though most of this analysis is dealt with in my website.
Pitt Archive FTP. Bishop's Opening Zip PGN File via FTP. 1998.
________. Various materials on the Urusov Gambit and on Prince Urusov, prepared by Max Burkett. 1997.
Forintos, Gyozo and Ervin Haag. The Petroff Defense. New York: Macmillan 1991.
I mention this because it was once widely available and you may have a copy. I think it is the best book on the Petroff, not least because it is one of the only to offer coverage of the Urusoff Gambit.
Galberg-Lund, Soren. Urusovuv Gambit. Brno: Self published 1995. Available from Chess Digest. An English translation of Galber-Lund's pamphlet was available as The Urusoff Gambit and is therefore in the Archive. It is a terrible translation of likely terrible prose, but it does actually have a couple game references of value. It is mostly supplanted by the materials above.
There is also some deep analysis of Avrukh-Skripchenko, Linares 2001, by GM Lukacs in Chess Base Magazine (which Polgar alludes to as her source for notes on the game) and a part of Neishtadt's book "Winning Quickly as White" which discusses the Gipslis game I think--though I don't have either handy to give you more specific citation information. I could also give you a lengthy bibliography of material related to the Open Two Knights Defense with 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nc6 4.d4 (to which the Urusov often transposes), but direct you for now to my incomplete bibliography at my Perreux Variation site.