You do not need to make a phone call, only need through the network, can finish all reservations.
Has a look the actual example :

First step Submits the order form , Below is the order form style which we receives:

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Second step Within 24 hours to confirm your reservation, Below Confirms the single example :

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Third step Payment. If you use a credit card, then this step automatically. View Payment

Fourth step Boarding Certificate , The sample of Boarding Certificate following :
More about Boarding Certificate

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