During Abolition 5/13, I made reference to the Marx-Bakunin matter. Let me elaborate here.
The “conspectus” (or critical notes) of Marx after his reading of Bakunin’s book Statism and Anarchy in Russian were written in 1874-1875 in the course of the polemic following the dissolution of the First International, therefore they are exactly contemporary with the Notes on the Gotha Program (and in fact there is a direct relationship because Bakunin identifies Marx’s “statist” socialism with Lassalle at the very moment when Marx is trying to distance himself from the Lassalians by reinstating his idea that the withering away of the state is the ultimate goal of communism, so it is a completely triangular confrontation).
But, whereas the Notes on the Gotha Program were left unpublished by Marx (later published by Engels in the course of later “programmatic” discussions in the German Social-democracy), the notes on Bakunin we published in a Russian journal only in the ‘20s and then in the Complete Works as “literarisches Nachlass”.
As for the notes themselves, you can find them in German (here) and as a partial translation in English. The French exists in a post-68 publication, a paperback edition which falls apart as soon as you use it… (I gave my copy to a young student a long time ago).
I recall a letter from Marx where he exclaims: “I am the true anarchist!”, but I can’t retrieve the exact reference now because it is in a volume that I don’t have with me now; however, I discussed similar statements and argued for the idea of Marx being caught in a “double bind” between Lassalle and Bakunin (which remains in subsequent Marxism) in a subchapter of my book La crainte des masses, which you can find here in French. A different argument (based on other episodes) which I find extremely valuable is to be found in the beautiful book by Mighel Abensour La démocratie contre l’Etat (there is an English version).
Finally, you can also find here the chapter from Wallerstein to which I alluded, on the contradictory attitude of all “ideologies” with respect to the “State vs Society” dilemma, which I find really illuminating.