Ошибка зависимости при установке curl

Я хотел установить curl для программирования на C. Однако я столкнулся с проблемой зависимости:

$ sudo apt-get install libcurl4-openssl-dev
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
 libcurl4-openssl-dev : Depends: librtmp-dev but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

Я попытался установить зависимости и получил эту ошибку:

$ sudo apt-get install libgnutls-dev
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
 libgnutls-dev : Depends: libgnutls-openssl27 (= 2.12.23-12ubuntu2.1) but 3.2.16-1ubuntu2.1ppa1~trusty is to be installed
E: Unable to correct problems, you have held broken packages.

Я проверил libgnutls-openssl27 версию на 3.2.16-1ubuntu2.1ppa1 ~ trusty.

Любая помощь?