Choral Singing Dataset (CSD): 

Multi-track dataset of choral music, recorded in collaboration with the Cor Anton Bruckner from Barcelona. 16 singers (4 sopranos, 4 altos, 4 tenors, 4 basses) recorded with individual microphones singing together. Each section was recorded separately, but in sync with the others thanks to a reference backing track and a video recording of the conductor of the choir.
This dataset contains F0 annotations (automatically extracted and manually corrected) for each individual microphone, note annotations, and sync MIDI files.

This dataset was released together with the following paper:

Helena Cuesta, Emilia Gómez, Agustín Martorell and Felipe Loáiciga. “Analysis of Intonation in Unison Choir Singing”. In Proceedings of the 15th International Conference on Music Perception and Cognition / 10th Triennial Conference of the European Society for the Cognitive Sciences of Music. Graz (Austria), July, 2018.

Dagsthul ChoirSet (DCS): 

Multi-track dataset of choral music, recorded during a Dagstuhl Seminar on “Computational Methods for Melody and Voice Processing in Music Recordings”. This dataset is a joint project with the International Audio Laboratories Erlangen (AudioLabs), Germany.

Following a similar configuration to the CSD, the Dagsthul ChoirSet consists of recordings of a choir of 13 singers, captured using a different microphones: larynx, headset and dynamic microphones for individual singers, and a stereo pair to capture the full choir. 
This dataset contains F0 annotations (automatically extracted using two different methods) for each individual microphone, beat annotations, and sync score representations.

The dataset was released together with the following paper:
Sebastian Rosenzweig, Helena Cuesta, Christof Weiß, Frank Scherbaum, Emilia Gómez, and Meinard Müller. “Dagstuhl ChoirSet: A Multitrack Dataset for MIR Research on Choral Singing.” In
Transactions of the International Society for Music Information Retrieval, 3(1), pp. 98–110, 2020.

Software 

Python repository for multiple F0 estimation in vocal ensembles

https://github.com/helenacuesta/multif0-estimation-polyvocals

 https://github.com/helenacuesta/DCStoolbox