A reader can find detailed accounts of Lakota ceremony without difficulty, and that availability is the problem this article exists to describe.
The early twentieth century produced published accounts of Lakota religion built from interviews with a small number of elderly men, conducted through interpreters, by collectors working within the assumptions of their period. Those accounts became standard, were quoted for decades, and have since been the subject of sustained argument about how much of their systematising structure came from the people interviewed and how much from the men writing it down.
A second and larger body of material came later, through popular books that presented Lakota spirituality to a general readership. Their effect was to make ceremonies widely known, widely imitated and, in several documented cases, sold. The Lakota Summit V declaration of June 1993 was a direct response, objecting by name to the conduct of these ceremonies by non-Lakota and to their commercial use.
The tradition's own transmission runs through instruction, through relationship with a person qualified to teach, and through participation. It is not, and was never intended to be, a body of information transferable by reading.
The atlas therefore names the institutions, records the structure, states that the material is restricted, and reproduces none of it. That a thing is in print is not evidence that it was ever meant to be.