Typed states for the displayed outbound observations.
Source: paper_references, paper_reference_links, observed 2026-08-14T12:13:26.613709Z
Paper Citation Record · LEDGER
As of 16 August 2026, this Paper Citation Record lists 45 of 45 outbound references and 0 inbound Pith citation observations for arXiv:1908.07949.
A citation records a reference. It does not transfer a finding from one paper to another.
Typed states for the displayed outbound observations.
Source: paper_references, paper_reference_links, observed 2026-08-14T12:13:26.613709Z
One-hop event checks from named stored sources.
Source: scholarly_work_events, retraction_status_cache, observed 2026-08-15T06:32:42.880941+00:00
Pith citing papers itemized under the disclosed page cap.
Source: paper_references, paper_reference_links
A source-named dated measurement, never combined with another source.
Source: cited_works
45 of 45 outbound references displayed
External citation measurements
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Observation 0c66e63b-76df-41b5-93b5-88db3aa46002 · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Assimilation of operational data
Reference 1
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Observation d35d8966-3df7-4b50-b290-8b35fd414e21 · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Eigenvalue estimates for preconditioned saddle point matrices
Reference 2
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation H., and Liesen, J
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Inexact constraint preconditioners for linear systems arising in interior point methods
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Observation de76f6de-36ae-4747-b49c-178dea8ae7b4 · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Unresolved cited work
Reference 5
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Unresolved cited work
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation J., and Zhang, Y
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation A strategy for operational implementation of 4D- Var, using an incremental approach
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Observation c6701472-f85e-4ea6-ba94-21c93157b34b · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Atmospheric Data Analysis , vol
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Observation 0ee97f11-357f-46cc-91ad-2f6b7765d834 · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Conditioning of the weak-constraint variational data assi milation problem for numerical weather prediction
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Observation 4da30ebb-6300-487b-a8a5-b0c398e90411 · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Variational data assimilation for tropospheric chemistry modeling
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Observation 1e6553d2-04d1-4ebf-ac04-f0a8edd29375 · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Minimization algorithms for variational data assimilation
Reference 12
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Observation e96b9676-c5a2-4ff3-aa18-3d339e4b2efd · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Parallelisation in the time dimension of four-dimensional variational da ta assimi- lation
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Observation 576b1959-fe57-4d43-96d1-0211e87516d8 · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation A., and Green, D
Reference 14
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation H., and V an Loan, C
Reference 15
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Observation cf91aee5-1862-4e98-8d77-65644fa66bba · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Unresolved cited work
Reference 16
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Observation 84e48006-e6a5-4d06-8d2d-dabf759928de · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Approximate gauss-newton methods for nonlinear least squares problems
Reference 17
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Observation 7e39d013-830c-4b5a-ba25-2c1e571cf090 · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Any nonincreasing convergence curve is possible for GMRES
Reference 18
Source-reported events for the cited work
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Observation 43eb7573-81a8-4ff0-b9c4-d4e9720a47e6 · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Bounds on eigenvalues of matrices arising from interior-point methods
Reference 19
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Adjoint methods in data assimilation for estimating model error
Reference 20
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation R., and Stiefel, E
Reference 21
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Reference 22
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Observation 90ffae0d-d36b-4960-abbe-c37fe7c55e19 · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation J., and Nichols, N
Reference 23
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Observation ce1fc4c4-a381-4f4e-977a-50693bd59e7b · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Atmospheric Modeling, Data Assimilation and Predictabili ty
Reference 24
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Observation 2d291631-59c7-4591-8869-dfef43830ade · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Variational data assimilation for very large environmental problems
Reference 25
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Observation 338cdb31-e391-4d53-a1a3-63f0b4518408 · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Predictability - a problem partly solved
Reference 26
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Observation 3afcb9d2-944b-4e26-bbfd-b1141c2480e9 · outbound
Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Spectral estimates for unreduced symmetric KKT systems arising from interior point methods
Reference 27
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation A comparison of reduced and unreduced KKT systems arising from interior point methods
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation J., and Diekman, C
Reference 29
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Unresolved cited work
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Unresolved cited work
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation C., and Saunders, M
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation A preconditioned iterative method for saddlepoint problems
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Unresolved cited work
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Fast iterative solution of stabilised Stokes systems
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Determinants of block matrices
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Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation Unresolved cited work
Reference 39
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No inbound Pith citation observations are available.