combine filter and expandSubcollections in REST query with curl

Following Jason's great article at https://devcentral.f5.com/articles/demystifying-icontrol-rest-part-3-how-to-pass-query-parameters-and-tmsh-options I'm trying to use some of the built in features of the REST API. To be more specific, I'm trying to get all ltm pools of a specific partition with expanded subCollections, thus listing all pool members currently in use. Therefore, I was planning to combine $filter+eq+partitionname and expandSubcollections=true in one query. However, I cannot figure out how to combine both of them...

This works:

curl -sk -u admin:password https://mymachine/mgmt/tm/ltm/pool?\$filter=partition%20eq%20mypartition

...so does this:

curl -sk -u admin:password https://mymachine/mgmt/tm/ltm/pool?expandSubcollections=true

But THIS does not work - it does not expand the members subcollection plus it creates some malformed JSON return string (when piping the return through json_xs, it gives back "malformed JSON string, neither array, object, number, string or atom, at character offset 0 (before "(end of string)") at /usr/bin/json_xs"):

curl -sk -u admin:password https://mymachine/mgmt/tm/ltm/pool?\$filter=partition%20eq%20mypartition&expandSubcollections=true

Neither does THIS work...

curl -sk -u admin:password https://mymachine/mgmt/tm/ltm/pool?expandSubcollections=true&\$filter=partition%20eq%20mypartition

... it returns:

If '$filter=partition%20eq%20mypartition' is not a typo you can run the following command to lookup the package that contains the binary:
command-not-found $filter=partition%20eq%20mypartition
-bash: $filter=partition%20eq%20mypartition: command not found
{"code":400,"message":"Query parameter $expandSubcollections is invalid.","errorStack":[]}

The last one seems to be a matter of escape sequences - somehow bash is interpreting the $filter part as a command on its own. Can anybody please point out how to combine those query parameters into one valid query? Many thanks in advance!