Distributed snapshots, as introduced by Chandy and Lamport in the context of asynchronous failure-free message-passing distributed systems, are consistent global states in which the observed distributed application might have passed through. It appears that two such distributed snapshots cannot necessarily be compared (in the sense of determining which one of them is the " first "). Differently , snapshots introduced in asynchronous crash-prone read/write distributed systems are totally ordered, which greatly simplify their use by upper layer applications. In order to benefit from shared memory snapshot objects, it is possible to simulate a read/write shared memory on top of an asynchronous crash-prone message-passing system, and build then snapshot objects on top of it. This algorithm stacking is costly in both time and messages. To circumvent this drawback, this paper presents algorithms building snapshot objects directly on top of asynchronous crash-prone message-passing system. " Directly " means here " without building an intermediate layer such as a read/write shared memory ". To the authors knowledge, the proposed algorithms are the first providing such constructions. Interestingly enough, these algorithms are efficient and relatively simple.