The phrase "especially those which" is correct and usable in written English.
You can use it to emphasize the ones in a particular group that you're talking about, or to contrast a particular group with others. For example: "I love all animals, especially those which are cats".
Especially those which makes demands of #ECB and #EU.
Some of these groups, especially those which dwelled on the corruption of the Church, were prosecuted.
Parasites can also play into this, especially those which cause severe limb deformation.
She was unhappy with Ryan's austere budgets, especially those which cut assistance to workers affected by free trade.
Much effort has been devoted to discover and study inhibitors of CDKs, especially those which display selectivity towards specific CDKs.
Look for Mr. Perry to emphasize his own conservative credentials — especially those which might appeal to religious voters.
Whatever the case, comment threads, especially those which attract many hundreds of participants, can be tough to read and to make sense of.
This money would then go towards subsidising adaptation projects in developing countries, especially those which are or will be severely effected by the consequences of climate change.
There is no denying the brutality of "The Wrestler," and some of the scenes in the ring, especially those which provoke the cardiac arrest, are hard to watch.
Still, many programs, especially those which claim to lead to high-paying jobs, use deceptive recruiting practices that both overstate graduates' employment prospects and understate students' financial obligations.
The estimation method proposed arises from the need to program the recovery plans for old towns, especially those which are abandoned.
