How to get WorkItemHandle from ChangeSetHandle?

Hi,
I'd like to know how to get WorkItem(Handle) associated with ChangeSet(Handle)...

String linkSummary = null;
for(Iterator<IChangeSetHandle> csIter = cshl.iterator(); csIter.hasNext();){
IChangeSetHandle tempCs = csIter.next();
IChangeSet contribution = (IChangeSet) repo.itemManager().fetchCompleteItem(tempCs, IItemManager.DEFAULT, null);
IContributor author = (IContributor) repo.itemManager().fetchCompleteItem(contribution.getAuthor(), IItemManager.DEFAULT, null);

Collection<IChangeSetHandle> cshc = new ArrayList<IChangeSetHandle>();
cshc.add((IChangeSetHandle)tempCs);
List<IChangeSetLinkSummary> cslsl = wm.getChangeSetLinkSummary(cshc, null);
for (IChangeSetLinkSummary csls : (List<IChangeSetLinkSummary>) cslsl) {
linkSummary = csls.getSummary();
System.out.println("Change Set Link Summary: " + linkSummary);

List<ILinkHandle> lhl = csls.getLinks();
for (ILinkHandle lh : lhl)
{
...