which, in turn vs which in turn

Some examples from the web:

• Sep 16, 2009 ... i am cofused about meaning of 'which in turn'<<--(is this correct sentence?)^^;; Also, i don't know when i use 'which in turn' please, teach me ...
• Apr 26, 2014 ... Money can be exchanged for goods or services [ that fulfill people's needs and wants ] [ which in turn bring happiness ]. a) Money can be ...
• The vassals were subject to their lords, who in turn were subject to barons or kings. My car was hit by a truck, which in turn was hit by the van. Mr. X leaked the  ...
• Learning is a result of listening, which in turn leads to even better listening and attentiveness to the other person. In other words, to learn from the child, we must  ...

Some examples from the web:

• External conditions generated a sudden downturn which in turn necessitated the adoption of drastic containment countermeasures.
• It made his blood pressure skyrocket, which in turn...
• A normal and varied diet contains many ingredients, which in turn contain many substances.
• A normal and varied diet contains many ingredients which in turn contain many substances.
• This has led to a deterioration of the balance between supply and demand which in turn puts producers' prices and incomes under pressure.
• Garbage attracts all kinds of germs, which in turn cause diseases.
• It caused a paraneoplastic neurologic syndrome, which in turn caused your blindness and coma.
• Intellectual property rights are a major prerequisite for developing new industries which in turn support job creation.
• Finally, the merger process may lead to elevated operational risks, which in turn might require further capital.
• EACEA is able to attract and retain highly qualified personnel, which in turn provides staffing stability.
• It also brings about openness, which in turn produces security.
• The measures in question consist of payments made by the Länder of Berlin and Brandenburg, which in turn receive funds for regional rail passenger transport from the Federal State.
• All lower level constituents are by definition subfields, which in turn, may be basic or compound.
• Furthermore, Bank Rossiya has important stakes in the National Media Group which in turn controls television stations which actively support the Russian government's policies of destabilisation of Ukraine.
• Greater transparency prevents inaccurate assessments, which in turn lead to bad investments - something we all wish to avoid.
• The impossibility of mergers has kept our air services market fragmented, which in turn has nibbled away at our airlines' competitiveness and led to high prices.
• Its fundamental objective is to raise the standard of living which in turn is a precursor to the equal treatment of citizens.
• The scope of this amendment is to promote a good level of interoperability, which in turn will determine a greater choice for end-users.
• Greece has revised its national account data, which in turn have been re-revised by Eurostat and the GNI Committee.
• And this culture is 'shaped' by an instrument that is the cornerstone of our individual and collective consciousness, which in turn creates a European hope.