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Would you please help me choose better options:

Even a Croatian author XY indicates/refers to the importance of (the existence) of standard/well-established procedure for the preparations as well as the importance of application of certain tried/? (that have been tried already) models/patterns of leading business negotiation. In this approach he also sees one of the sources of negotiating strength/power of multinational companies, especially in negotiating with business partners from less developed countries/countries with less developed markets.

Thank you
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My take:

Even the Croatian author, XY, mentions the importance of following standard preparatory procedures and of applying certain established models for leading business negotiations. In this approach, he also sees one of the sources of the negotiating strength/power of multinational companies, especially in negotiating with business partners from countries with less-developed markets.
(Either strength or power, for my money.)
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Thank you Mr Micawber. I appreciate your help. If you ever need blood or a kidney, let me know:)
It's me, Antonia, by the way.