"open freely" is a correct and usable phrase in written English.
It means that something can be opened easily without any resistance or difficulty. Example: The window was stuck but after applying some oil, it opened freely.
Archnet is an open, freely accessible, digital library.
After thousands of cuts a day your fingers no longer open freely.
Open freely to every child and upheld by public funds, it was to be a lay institution under the sovereignty of the state, the archetype of the present-day American public school.
It is of no avail to open freely our ports for articles of small and trifling consumption, to open our trade to small and comparatively unimportant specks on the ocean;—if we will really extend our trade, we must be willing to take freely and regularly articles of extensive consumption from countries of wide and rich territory, having great wants.
He questioned the council as to why tickets were being sold for a viewing area previously open freely to the public, when the council had yet to officially make a decision on whether that space would be handed over to race promoters.
Hard part was to find high quality open freely usable format.. has joined the list.
The third lesson learnt is the " relevance of developing open, freely-accessible sources of knowledge".
Go outside and ensure the outside vent opens freely and remove any accumulated lint, spider webs, etc.
The LAND-deFeND database structure is open, and freely available from http://geomorphology.irpi.cnr.it/tools.irpi.cnr.it/tools
Both projects are open source, freely available software developed by the corresponding author of this paper.
The OGR is an open resource freely accessible at http://webtom.cabgrid.res.in/ogr/.in/ogr/
