Clarke was sacked after the Royals fell to a last-gasp defeat to Queens Park Rangers in the Championship last week.
The loss meant that the club had won just one of their last eight games, and dragged them well into the mid-table battle that - already at this stage of the season - looks to be fighting over just one play-off spot, as the top five begin to get away from the rest.
Sky Sports report that Reading have been put off moving for former Leicester City manager Nigel Pearson, as he is too expensive.
However, the club are keeping their eye on Stubbs and Rowett, who are both impressing at their respective clubs.
While Birmingham have endured a poor run - having lost their last three - Rowett has undoubtedly done a fantastic job at St Andrew's, having taken over when the side found themselves in the Championship's bottom three. Like Reading, they currently find themselves in that mid-table fight.
In contrast, Hibs' form has been sensational over the past couple of months. Since losing two of their first three games in the Scottish Championship, Stubbs' men have enjoyed a 12-match unbeaten run. That form has seen them sit just three points behind league leaders Rangers.