Sequential History in Herlihy and Wing's Linearizability paper

I've been reading Herlihy and Wing's paper Linearizability: A Correctness Condition for Concurrent Objects (ACM Transactions on Programming Languages and Systems, 12(3):463–492, 1990; PDF) and there's one piece of the paper that is a fairly small detail, but on which I'm stuck anyway. They define a sequential history as one satisfying two conditions:

• First event of $H$ is an invocation

• Each invocation, except possibly the last, is immediately followed by a matching response. Each response is immediately followed by a matching invocation.

Question 1 Since an invocation and response match iff they have the same object and process, does "each response is immediately followed by a matching invocation" imply that all events in a sequential history share the same object and process (since each event matches the prior event)?

Question 2 Later in section 2, they offer the following as an example of a sequential history, even though it involves multiple processes:

q Enc(x) A
q Ok() A
q Enq(y) B
q Ok() B
q Deq() B
q Ok(x) B
q Deq() A
q Ok(y) A
q Enq(z) A
q Ok() A

I suspect that the definition of sequential history actually doesn't include the constraint "each response is immediately followed by a matching invocation" but maybe it does and I'm just misreading it. In either case, thanks for any enlightenment anyone can provide!

I'm stuck on the same detail and luckily found your post. Agree that the word "matching" in "Each response is immediately followed by a matching invocation" should be omitted. The evidence is that the word is omitted in the paper, Axioms for concurrent objects, by the same authors. Link:
http://www.cs.cmu.edu/~wing/publications/HerlihyWing87a.pdf

StackExchange Computer Science Q#83638, answer score: 2