deletions | additions       diff --git a/A_contactless_interaction_is_the__.tex b/A_contactless_interaction_is_the__.tex  index fc13dcb..b562d41 100644  --- a/A_contactless_interaction_is_the__.tex  +++ b/A_contactless_interaction_is_the__.tex 
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A contactless interaction is the simplest form of collaboration, typically involving an exchange of information or commands implicitly associated to the shared task. The collaboration request can be communicated using gestures, vocal commands, or a combination of the two. When the human request is done with a gesture (e.g., hand waving in the presented experiments), his/her collaborative part is the one used for the gesture. If voice were used, the collaborative part can be expressed in the vocal command (e.g., 'follow the right hand’) or combined with the gesture (e.g., 'follow the hand’, showing the right hand) as seen in Figure 20. 18.