Online First Articles are fully citable: they have been allocated DOIs even though they have not been assigned yet to a specific issue.   Journal Home Journal Content Guidelines Editorial Board Aims and Scope Subscriptions Search in this journal Online Submission Online Peer Review This journal is part of the fourth subject package of the Karger Journal Archive Collection Information on packages (PDF) Free sample issues For non-native English speakers and international authors who would like assistance with their writing before submission, we suggest American Journal Experts for their scientific editing service.  © 2009 S. Karger AG, Basel